Edit File: 00FAQ
Frequently Asked Questions about lsof ********************************************************************** | The latest release of lsof is always available via anonymous ftp | | from lsof.itap.purdue.edu. Look in pub/lsof.README for its | | location. | ********************************************************************** ______________________________________________________________________ This file contains frequently asked questions about lsof and answers to them. Vic Abell <abe@purdue.edu> March 25, 2009 ______________________________________________________________________ Table of Contents: 1.0 General Concepts 1.1 Lsof -- what is it? 1.2 Where do I get lsof? 1.2.1 Are there mirror sites? 1.2.2 Are lsof executables available? 1.2.3 How do I check the validity of an lsof distribution? 1.2.4 Why can't I get the sum(1) result reported in README.lsof_<revision>? 1.2.5 Why won't gpg accept the lsof-signing PGP public key? 1.3 Where can I get more lsof documentation? 1.4 How do I report an lsof bug? 1.5 Where can I get the lsof FAQ? 1.5.1 How timely is the on-line FAQ? 1.6 Is there a test suite? 1.7 Is lsof vulnerable to the standard I/O descriptor attack? 1.8 Can I alter lsof's make(1) behavior? 1.9 Is there an lsof license? 1.10 Language locale support 1.10.1 Does lsof support language locales? How do I use the support? 1.10.2 Does lsof support wide characters in language locales? 1.11 Are any files in the lsof distribution copyrighted? 1.12 Are there other lsof-related resources? 2.0 Lsof Ports 2.1 What ports exist? 2.2 What about a new port? 2.2.1 User-contributed Ports 2.3 Why isn't there an AT&T SVR4 port? 2.4 Why isn't there an SGI IRIX port? 2.5 Why does lsof's Configure script report "WARNING: unsupported dialect or version"? 3.0 Lsof Problems 3.1 Configuration Problems 3.1.1 Why can't Configure determine the UNIX dialect version? 3.2 Compilation Problems 3.2.1 Why does the compiler complain about missing header files? 3.2.2 Why does gcc complain about the contents of header files distributed by the system's vendor? 3.2.3 Other header file problems 3.3 Why doesn't lsof report full path names? 3.3.1 Why do lsof -r reports show different path names? 3.3.2 Why does lsof report the wrong path names? 3.3.3 Why doesn't lsof report path names for unlinked (rm'd) files? 3.3.4 Why doesn't lsof report the "correct" hard linked file path name? 3.3.5 When will lsof report path names for deleted files? 3.4 Why is lsof so slow? 3.5 Why doesn't lsof's setgid or setuid permission work? 3.6 Does lsof have security problems? 3.7 Will lsof show remote hosts using files via NFS? 3.8 Why doesn't lsof report locks held on NFS files? 3.8.1 Why does lsof report a one byte lock on byte zero as a full file lock? 3.9 Why does lsof report different values for open files on the same file system (the automounter phenomenon)? 3.10 Why don't lsof and netstat output match? 3.10.1 Why can't lsof find accesses to some TCP and UDP ports? 3.11 Why does lsof update the device cache file? 3.12 Why doesn't lsof report state for UDP socket files? 3.13 I am editing a file with vi; why doesn't lsof find the file? 3.14 Why doesn't lsof report TCP/TPI window and queue sizes for my dialect? 3.14.1 Why doesn't lsof report socket options, socket states, and TCP flags and values for my dialect? 3.14.2 Why doesn't lsof report the partial listen queue connection count for my dialect? 3.15 What does "no more information" in the NAME column mean? 3.16 Why doesn't lsof find a process that ps finds? 3.17 Why doesn't -V report a search failure? 3.18 Portmap problems 3.18.1 Why isn't a name displayed for the portmap registration? 3.18.2 How can I display only portmap registrations? 3.18.3 Why doesn't lsof report portmap registrations for some ports? 3.19 Why is `lsof | wc` bigger than my system's open file limit? 3.20 Why doesn't lsof report file offset (position)? 3.20.1 What does lsof report for size when the file doesn't really have one? 3.21 Problems with path name arguments 3.21.1 How do I ask lsof to search a file system? 3.21.2 Why doesn't lsof find all the open files in a file system? 3.21.3 Why does the lsof exit code report it didn't find open files when some files were listed? 3.21.4 Why won't lsof find all the open files in a directory? 3.21.5 Why are the +D and +d options so slow? 3.21.6 Why do the +D and +d options produce warning messages? 3.22 Why can't my C compiler find the rpcent structure definition? 3.23 Why doesn't lsof report fully on file "foo" on UNIX dialect "bar?" 3.24 Why do I get a complaint when I execute lsof that some library file can't be found? 3.25 Why does lsof complain it can't open files? 3.26 Why does lsof warn "compiled for x ... y; this is z."? 3.27 How can I disable the kernel identity check? 3.28 Why don't ps(1) and lsof agree on the owner of a process? 3.29 Why doesn't lsof find an open socket file whose connection state is past CLOSE_WAIT? 3.30 Why don't machine.h definitions work when the surrounding comments are removed? 3.31 What do "can't read inpcb at 0x...", "no protocol control block", "no PCB, CANTSENDMORE, CANTRCVMORE", etc. mean? 3.32 What do the "unknown file system type" warnings mean? 3.33 Installation 3.33.1 How do I install lsof? 3.33.2 How do I install a common lsof when I have machines that need differently constructed lsof binaries? 3.34 Why do lsof 4.53 and above reject device cache files built by earlier lsof revisions? 3.35 What do "like block special" and "like character special" mean in the NAME column? 3.36 Why does an lsof make fail because of undefined symbols? 3.37 Command Regular Expressions (REs) 3.37.1 What are basic and extended regular expressions? 3.37.2 Why can't I put a slash in a command regular expression? 3.37.3 Why does lsof say my command regular expression wasn't found? 3.38 Why doesn't lsof report on shared memory segments? 3.39 Why does lsof report two instances of itself? 3.40 Why does lsof report '\n' in device cache file error messages? 3.41 Kernel Symbol and Address Problems 3.41.1 What does "lsof: WARNING: name cache hash size length error: 0" mean? 3.41.2 Why does lsof produce "garbage" output? 3.42 Why does lsof report open files when run as super user that it doesn't report when run with lesser privileges? 3.43 Test Suite Problems 3.43.1 Errors all tests can report: 3.43.1.1 Why do tests complain "ERROR!!! can't execute ../lsof"? 3.43.1.2 Why do tests complain "ERROR!!! can't find ..." a file? 3.43.1.3 Why do some tests fail to compile? 3.43.1.4 Why do some tests always fail? 3.43.1.5 Why does the test suite say it hasn't been validated on my dialect? 3.43.1.6 Why do the tests complain they can't stat() or open() /dev/mem or /dev/kmem? 3.43.2 LTbigf test issues 3.43.2.1 Why does the LTbigf test say that the dialect doesn't support large files? 3.43.2.2 Why does LTbigf complain about operations on its config.LTbigf* file? 3.43.2.3 Why does LTbigf warn that lsof doesn't return file offsets? 3.43.3 Why does the LTbasic test complain "ERROR!!! lsof this ..." and "ERROR!!! lsof that ..."? 3.43.4 LTnfs test issues 3.43.4.1 Why does the LTnfs test complain "couldn't find NFS file ..."? 3.43.5 LTnlink test issues 3.43.5.1 Why does the LTnlink test complain that its test file is on an NFS file system? 3.43.5.2 Why does LTnlink delay and report "waiting for link count update: ..."? 3.43.6 LTdnlc test issues 3.43.6.1 Why won't the LTdnlc test run? 3.43.6.2 What does the LTdnlc test mean by "... <path> found: 100.00%"? 3.43.6.3 Why does the DNLC test fail? 3.43.7 Why hasn't the test suite been qualified for 64 bit HP-UX 11 when lsof is compiled with gcc? 3.43.8 LTszoff test issues 3.43.8.1 Why does LTszoff warn that lsof doesn't return file offsets? 3.43.9 LTlock test issues 3.44 File descriptor list (the ``-d'' option) problems 3.44.1 Why does lsof reject a ``-d'' FD list? 3.44.2 Why are file descriptors other than those in my FD list reported? 3.45 How can I supply device numbers for inaccessible NFS file systems? 3.46 Why won't lsof find open files on over-mounted file systems? 3.47 What can be done when lsof reports no more space? 3.48 What if the lsof build encounters ar and ld problems? 4.0 AIX Problems 4.1 What is the Stale Segment ID bug and why is -X needed? 4.1.1 Stale Segment ID APAR 4.2 Gcc Work-around for AIX 4.1x 4.3 Gcc and AIX 4.2 4.4 Why won't lsof's Configure allow the use of gcc for AIX below 4.1? 4.5 What is an AIX SMT file type? 4.6 Why does AIX lsof start so slowly? 4.7 Why does exec complain it can't find libc.a[shr.o]? 4.8 What does lsof mean when it says, "TCP no PCB, CANTSENDMORE, CANTRCVMORE" in a socket file's NAME column? 4.9 When the -X option is used on AIX 4.3.3, why does lsof disable it, saying "WARNING: user struct mismatch; -X option disabled?" 4.10 Why doesn't the -X option work on my AIX 5L or 5.[123] system? 4.11 Why doesn't /usr/bin/oslevel report the correct AIX version? 4.11.1 Why doesn't /usr/bin/oslevel report the correct AIX version on AIX 5.1? 4.12 Why does lsof for AIX 5.1 or above Power architecture complain about kernel bit size? 4.13 What can't gcc be used to compile lsof on the ia64 architecture for AIX 5 and above? 4.14 Why does lsof get a segmentation fault when compiled with gcc for a 64 bit Power architecture AIX 5.1 kernel? 4.15 Why does lsof ignore AFS on my AIX system? 4.16 Why does lsof report "system paging space is low" and exit? 4.17 Why does lsof have compilation and execution problems on AIX 5.3 above maintenance level 1? 5.0 Apple Darwin Problems 5.1 What do /dev/kmem-based and libproc-based mean? 5.2 /dev/kmem-based Apple Darwin Questions 5.2.1 Why does Configure ask for a path to the Darwin XNU kernel header files? 5.2.1.1 Why does Configure complain that Darwin XNU kernel header files are missing? 5.2.2 Why doesn't Apple Darwin lsof report text file information? 5.2.3 Why doesn't Apple Darwin lsof support IPv6? 5.2.4 Why does lsof complain about a mismatch between the release for which lsof was compiled and the booted Mac OS X release? 5.2.5 Why does lsof for Apple Darwin 8 and higher report "stat(...): ..." in the NAME column? 5.2.6 What are the limitations of Apple Darwin lsof link count reporting? 5.3 Libproc-based Apple Darwin Questions 6.0 BSD/OS BSDI Problems 6.0.5 Statement of deprecation 7.0 DEC OSF/1, Digital UNIX, and Tru64 UNIX Problems 7.1 Why does lsof complain about non-existent /dev/fd entries? 7.2 Why does the Digital UNIX V3.2 ld complain about Ots* symbols? 7.3 Why can't lsof locate named pipes (FIFOs) under V3.2? 7.4 Why does lsof use the wrong configuration header files? For example, why can't the lsof compilation find cpus.h? 7.5 Why does lsof indicate incomplete paths with " -- " for Tru64 UNIX 5.1 files? 7.6 Why doesn't lsof report link count, node number, and size for some Tru64 5.x CFS files? 7.7 Why does lsof say it can't read the kernel name list or proc table on Digital UNIX 4.x or Tru64 UNIX? 8.0 FreeBSD Problems 8.1 Why doesn't lsof report on open kernfs files? 8.2 Why doesn't lsof work on my FreeBSD system? 8.3 Why doesn't lsof work on the RELEASE version of CURRENT? 8.4 Why can't kvm_open() can't find some file? 8.5 FreeBSD ZFS Problems 8.5.1 Why does FreeBSD lsof report "WARNING: no ZFS support has been 8.6 Why can't Configure create lsof_owner.h for FreeBSD 6 and above? 8.6.1 Why are there lockf structure compiler errors for FreeBSD 6.0 and higher lsof? 8.6.2 Why don't /usr/src/sys/sys/lockf.h and /usr/include/sys/lockf.h match? 9.0 HP-UX Problems 9.1 What do /dev/kmem-based and PSTAT-based mean? 9.2 /dev/kmem-based HP-UX lsof Questions 9.2.1 Why doesn't a /dev/kmem-based HP-UX lsof compilation use -O? 9.2.2 Why doesn't the /dev/kmem-based CCITT support work under 10.x? 9.2.3 Why can't /dev/kmem-based lsof be compiled with `cc -Aa` or `gcc -ansi` under HP-UX 10.x? 9.2.4 Why does /dev/kmem-based lsof complain about no C compiler? 9.2.5 Why does Configure complain about q4 for /dev/kmem-based lsof for HP-UX 11? 9.2.6 When compiling /dev/kmem-based lsof for HP-UX 11 what do the "aCC runtime: ERROR..." messages mean? 9.2.7 Why doesn't /dev/kmem-based lsof for HP-UX 11 report VxFS file link counts, node numbers, and sizes correctly? 9.2.8 Why can't /dev/kmem-based lsof be built with gcc for 64 bit HP-UX 11? 9.2.8.1 How can I acquire a gcc for building lsof for 64 bit HP-UX 11? 9.2.9 Why does /dev/kmem-based lsof for HP-UX 11 report "unknown file system type" for VxFS files? 9.2.10 Why does the ANSI-C compiler complain about comments in HP-UX 11 header files? 9.2.11 Why does dnode1.c cause the HP-UX 11 compiler to complain that <sys/fs/vx_inode.h> is missing or incorrect? 9.3 PSTAT-based HP-UX lsof Questions 9.3.1 Why does PSTAT-based lsof complain about pst_static and other PSTAT structures? 9.3.2 Why does PSTAT-based lsof complain it can't read pst_* structures? 9.3.3 Why does PSTAT-based lsof rebuild the device cache file after each reboot? 9.3.4 Why doesn't PSTAT-based lsof report TCP addresses for telnetd's open socket files? 9.3.5 Why does PSTAT-based lsof cause an HP-UX 11.11 kernel panic? 9.3.6 Why doesn't PSTAT-based lsof report a CWD that is on a loopback (LOFS) file system? 9.3.7 Why do some swinstall packages for PSTAT-based HP-UX 11.11 packages complain about setgid and setuid bits? 9.3.8 Why won't the bundled C compiler build PSTAT-based lsof for PA-RISC HP-UX 11.23? 9.3.9 Why won't gcc build PSTAT-based lsof for PA-RISC HP-UX 11.23? 9.3.10 Why does PSTAT-based lsof complain, "FATAL: pst_stream_size should be: 672; is 72" on HP-UX 11.11 and above? 9.4 Why won't the HP-UX depot install? 10.0 Linux Problems 10.1 What do /dev/kmem-based and /proc-based lsof mean? 10.2 /proc-based Linux lsof Questions 10.2.1 Why doesn't /proc-based lsof report file offsets (positions)? 10.2.2 Why does /proc-based lsof report "can't identify protocol" for some socket files? 10.2.3 Why does /proc-based lsof warn about unsupported formats? 10.2.4 Why does /proc-based lsof report "(deleted)" after a path name? 10.2.5 Why doesn't /proc-based lsof report full open file information for all processes? 10.2.6 Why won't Customize offer to change HASDCACHE or WARNDEVACCESS for /proc-based lsof? 10.2.7 /proc-based lsof Linux NFS questions 10.2.7.1 Why can't lsof find files on an accessible NFS file system? 10.2.7.2 Why can't lsof find files on an inaccessible NFS file system? 10.2.8 Why doesn't /proc-based Linux lsof report socket options and values, socket state flags, and TCP options and values? 10.2.9 Does /proc-based Linux lsof use a device cache? 10.2.10 Why doesn't /proc-based Linux lsof report any or all file structure values for its +fcfgGn option? 10.3 Special Linux file types 10.3.1 Why is ``DEL'' reported as a Linux file type? 10.3.2 Why is ``unknown'' reported as a Linux file type? 10.4 Linux ``mem'' Entry Problems 10.4.1 What do ``path dev=xxx'' and ``path inode=yyy'' mean in the NAME column of Linux ``mem'' file types? 10.4.2 Why is neither link count nor size reported for some Linux ``DEL'' and ``mem'' file types? 10.5 Special Linux NAME column messages 10.5.1 What does ``(stat: xxx)'' mean in the NAME column of Linux files? 10.5.2 What does ``(readlink: xxx)'' mean in the NAME column of Linux files? 10.6 Why is ``NOFD'' reported as a Linux file type? 10.7 Why does Linux lsof report a NAME column value that begins with ``/proc''? 10.8 Linux /proc/net/tcp* and /proc/net/udp* issues 10.8.1 Why use the Linux -X option? 10.8.2 Why does lsof say ``-i is useless when -X is specified''? 10.8.3 Why does lsof say ``can't identify protocol (-X specified)''? 11.0 NetBSD Problems 11.1 Why doesn't lsof report on open kernfs files? 11.2 Why doesn't lsof report on open files on: file descriptor file systems; /proc file systems; 9660 (CD-ROM) file systems; MS-DOS (floppy disk) file systems; or kernel file systems? 11.3 Why does lsof produce confusing results for nullfs file systems? 11.4 NetBSD header file problems 11.4.1 Why can't the compiler find some NetBSD header files? 11.4.2 Why does NetBSD lsof produce incorrect output? 11.5 Why isn't lsof feature xxx enabled for NetBSD? 12.0 NEXTSTEP and OPENSTEP Problems 12.1 Why can't lsof report on 3.1 lockf() or fcntl(F_SETLK) locks? 12.2 Why doesn't lsof compile for NEXTSTEP with AFS? 13.0 OpenBSD Problems 13.1 Why doesn't lsof support kernfs on my OpenBSD system? 13.2 Will lsof work on OpenBSD on non-x86-based architectures? 13.3 <sys/pipe.h> problems 13.3.1 Why does the compiler claim nbpg isn't defined? 13.3.2 What value should I assign to nbpg? 13.4 Why doesn't lsof report on open MS-DOS file system (floppy disk) files? 13.5 Why isn't lsof feature xxx enabled for OpenBSD? 14.0 Output problems 14.1 Why do the lsof column sizes change? 14.2 Why does the offset have ``0t' and ``0x'' prefixes? 14.3 What are the values printed in the FILE_FLAG column and why is 0x<value> sometimes included? 14.3.1 Why doesn't lsof display FILE_FLAG values for my dialect? 14.4 Network Addresses 14.4.1 Why does lsof's -n option cause IPv4 addresses, mapped to IPv6, to be displayed in IPv6 notation? 14.5 Why does lsof output \x, ^x, or \xnn for characters sometimes? 14.5.1 Why is space considered a non-printable character in command names? 14.6 Why doesn't lsof print all the characters of a command name? 14.7 Why does lsof reject some -c command names, saying their lengths are "> what system provides (nn)"? 14.8 Why does lsof sometimes print TYPE numbers instead of names? 14.9 Marker line format problems 14.9.1 Why won't lsof accept a marker line format? 14.9.2 Why does lsof reject the NL (%n) marker line format? 14.10 How are protocol state name exclusion and inclusion used? 14.10.1 Why doesn't my dialect support state name exclusion and inclusion? 15.0 Pyramid Version Problems 15.0.5 Statement of deprecation 16.0 SCO Problems 16.1 SCO OpenServer Problems 16.1.1 How can I avoid segmentation faults when compiling lsof? 16.1.2 Where is libsocket.a? 16.1.3 Why do I get "warning C4200" messages when I compile lsof? 16.2 SCO|Caldera UnixWare Problems 16.2.1 Why doesn't lsof compile on my UnixWare 7.1.1 or above system? 16.2.2 Why does lsof complain about node_self() on my UnixWare 7.1.1 or above system? 16.2.3 Why does UnixWare 7.1.1 or above complain about -lcluster, node_self(), or libcluster.so? 16.2.4 Why does UnixWare 7.1.1 or above lsof complain it can't read the kernel name list? 16.2.5 Why doesn't lsof report link count, node number, and size for some UnixWare 7.1.1 or above CFS files? 16.2.6 Why doesn't lsof report open files on all UnixWare 7.1.1 NonStop Cluster (NSC) nodes? 16.2.7 Why doesn't lsof report the UnixWare 7.1.1 NonStop Cluster (NSC) node a process is using? 16.2.8 Why does the compiler complain about missing UnixWare 2.1[.x] header files? 17.0 Sun Problems 17.0.5 Statement of deprecation 17.1 My Sun gcc-compiled lsof doesn't work -- why? 17.2 How can I make lsof compile with gcc under Solaris 2.[456], 2.5.1, 7, 8 or 9? 17.3 Why does Solaris Sun C complain about system header files? 17.4 Why doesn't lsof work under my Solaris 2.4 system? 17.5 Where are the Solaris header files? 17.6 Where is the Solaris /usr/src/uts/<architecture>/sys/machparam.h? 17.7 Why does Solaris lsof say ``can't read proc table''? 17.8 Why does Solaris lsof complain about a bad cached clone device? 17.9 Why doesn't Solaris make generate .o files? 17.10 Why does lsof report some Solaris 2.3 and 2.4 lock types as `N'? 17.11 Why does lsof Configure say "WARNING: no cc in ..."? 17.12 Solaris 7, 8 and 9 Problems 17.12.1 Why does lsof say the compiler isn't adequate for Solaris 7, 8 or 9? 17.12.2 Why does Solaris 7, 8 or 9 lsof say "FATAL: lsof was compiled for..."? 17.12.3 How do I build lsof for a 64 bit Solaris kernel under a 32 bit Solaris kernel? 17.12.4 How do I install lsof for Solaris 7, 8 or 9? 17.12.5 Why does my Solaris 7, 8 or 9 system say it cannot execute lsof? 17.12.6 What gcc will produce 64 bit Solaris 7, 8 and 9 executables? 17.12.7 Why does lsof on my Solaris 7, 8 or 9 system say, "can't read namelist from /dev/ksyms?" 17.13 Solaris and COMMON 17.13.1 What does COMMON mean in the NAME column for a Solaris VCHR file? 17.13.2 Why does a COMMON Solaris VCHR file sometimes seem to have an incorrect minor device number? 17.14 Why don't lsof and Solaris pfiles reports always match? 17.15 Why does lsof say, "kvm_open(namelist=default, core=default): Permission denied?" 17.16 Why is lsof slow on my busy Solaris UFS file system? 17.17 Why is lsof so slow on my Solaris 8 or 9 system? 17.18 Solaris and VxFS 17.18.1 Why doesn't lsof support VxFS 3.4 on Solaris 2.6, and above? 17.18.2 Why does lsof report "vx_inode: vxfsu_get_ioffsets error" for open Solaris 2.6 and above VxFS 3.4 and above files? 17.18.3 Why does Solaris Configure claim there is no VxFS library? 17.18.4 Why doesn't Solaris lsof report VxFS path name components? 17.18.5 Why does Solaris 10 lsof report scrambled VxFS paths? 17.19 Large file problems 17.19.1 Why does lsof complain it can't stat(2) a Solaris 2.5.1 large file? 17.20 Why does lsof get a segmentation fault on 64 bit Solaris 8 using NIS+? 17.21 Will lsof crash the Solaris kernel? 17.22 Why does lsof on Solaris 7, 8, or 9 report a kvm_open() failure? 17.23 Solaris and SAM-FS 17.23.1 Why does Solaris lsof report "(limited SAM-FS info)"? 17.23.2 Why can't lsof locate named SAM-FS files? 17.24 Lsof and Solaris 10 zones 17.24.1 How can I make lsof list the Solaris zone? 17.24.2 Why doesn't lsof work in a Solaris 10 zone? 17.24.3 Why does lsof complain it can't stat() Solaris 10 zone file systems? 17.25 Solaris 10 problems 17.25.1 Why does Solaris 10 lsof sometimes report the wrong path name? 17.25.2 Why does Solaris 10 lsof sometimes report only the mounted-on directory and device? 17.25.3 What does "(deleted)" mean in the NAME column of a Solaris 10 open file? 17.25.4 What does "(?)" mean in the NAME column of a Solaris 10 open file? 17.26 Solaris contract file problems 17.26.1 Why doesn't lsof report size, link count and node number for Solaris 10 contract files? 17.26.2 Why can't lsof locate a Solaris 10 contract file by path name? 17.27 Solaris 10 ZFS probblems 17.27.1 Why does Configure ask for the location of ZFS header files? 17.27.2 Why do -h and -v output warn about possibly inaccurate ZFS structure definitions? 17.27.3 Why don't the Open Solaris ZFS header files provide correct ZFS kernel structure definitions? 18.0 Lsof Features 18.1 Why doesn't lsof doesn't report on /proc entries on my system? 18.2 How do I disable the device cache file feature or alter it's behavior? 18.2.1 What's the risk with a perverted device cache file? 18.2.2 How do I put the full host name in a personal device cache file path? 18.2.3 How do I put the personal device cache file in /tmp? 18.3 Why doesn't lsof know about AFS files on my favorite dialect? 18.3.1 Why doesn't lsof report node numbers for all AFS volume files, or how do I reveal dynamic module addresses to lsof? ______________________________________________________________________ 1.0 General Concepts 1.1 Lsof -- what is it? Lsof is a UNIX-specific tool. Its name stands for LiSt Open Files, and it does just that. It lists information about files that are open by the processes running on a UNIX system. See the lsof man page, the 00DIST file, the 00QUICKSTART file, and the 00README file of the lsof distribution for more information. 1.2 Where do I get lsof? Lsof is available via anonymous ftp from lsof.itap.purdue.edu. Look in the pub/tools/unix/lsof sub-directory. ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof Bzip2'd, compressed and gzip'd tar files with GPG certificates are available. 1.2.1 Are there mirror sites? On September 3, 2003 these sites appeared to mirror lsof: ftp://ftp.cerias.purdue.edu/pub/tools/unix/sysutils/lsof ftp://ftp.tau.ac.il/pub/unix/admin ftp://ftp.cert.dfn.de/pub/tools/admin/lsof ftp://ftp.fu-berlin.de/pub/unix/tools/lsof ftp://gd.tuwien.ac.at/utils/admin-tools/lsof ftp://sunsite.ualberta.ca/pub/Mirror/lsof 1.2.2 Are lsof executables available? Some lsof executables are available in the subdirectory tree pub/tools/unix/lsof/binaries These are neither guaranteed to be current nor cover every dialect and machine architecture. I don't recommend you use pre-compiled lsof binaries; I recommend you obtain the sources and build your own binary. Even if you're a Sun user without a Sun C compiler, you can use gcc to compile lsof. If you must use a binary file, please be conscious of the security and configuration implications in using an executable of unknown or different origin. The lsof binaries are accompanied by GPG certificates. Please use them! Three additional cautions apply to executables: 1. Don't try to use an lsof executable, compiled for one version of a UNIX dialect, on another. Patches can make the dialect version different. 2. If you want to use an lsof binary on multiple systems, they must be running the same dialect OS version and have the same patches and feature support. 1.2.3 How do I check the validity of an lsof distribution? There are two ways to check the validity of an lsof distribution: 1. Follow the instructions in the CHECKSUMS_<revision> file found with the lsof distribution. Checking with GPG is the best method. 2. Follow the instructions in the "Security" section of the README.lsof_<revision> file found inside the lsof distribution. Again, checking with GPG is the best method. 1.2.4 Why can't I get the sum(1) result reported in README.lsof_<revision>? The "Security" section of the README.lsof_<revision> file found inside the lsof distribution gives md5, sum, and GPG certificate information. The simplest, the sum(1) signature, seems to be the trickiest. That's because there are different sum(1) methods, BSD systems usually have cksum(1) instead of sum(1), and different systems compute the block size value differently. First, the lsof sum results are computed with the old, "alternate" algorithm. On newer systems, you can use sum's "-r" option to get that computation result. Second, on BSD systems you usually must use cksum(1) instead of sum(1), because they have no sum(1). To tell cksum(1) to use the old, "alternate" algorithm, use its "-o1" option. Third, the second value that sum reports, the block count, may be computed differently on different systems -- usually block size is considered to be 512 or 1,024. The lsof block counts were computed on a system with a sum(1) option that considers block size to be 512. The BSD system cksum(1) -o1 option considers block size to be 1,024. If your sum(1) or cksum(1) doesn't report a block count that matches the sum(1) signature given in README.lsof_<revision>, check its man page to see what block size it uses, then adjust its reported block count appropriately. 1.2.5 Why won't gpg accept the lsof-signing PGP public key? An older PGP key that once signed lsof distributions is included in lsof revisions prior to 4.70. The PGP key is indeed my key, but is incompatible with GPG. It was created about ten years ago and is still acceptable to PGP versions 2.6.2 through 6.5.2. Lsof revisions 4.70 and above are signed with a copy of my PGP key that has been made acceptable for use with GPG by importing it under GPG's "--allow-non-selfsigned-uid" option. You can find my GPG compatible key in lsof revisions 4.70 and above and at: ftp://lsof.itap.purdue.edu/pub/Victor_A_Abell.gpg If you have an older lsof revision with my PGP key, there are two possible ways to use it: * Use it with a PGP version from 2.6.2 through 6.5.2. * Use GPG's "--allow-non-selfsigned-uid" option when you import my PGP key into your GPG key ring. $ gpg --allow-non-selfsigned-uid --import Victor_A_Abell.pgp 1.3 Where can I get more lsof documentation? A significant set of documentation may be found in the lsof distribution (See "Where can I get lsof?). There is a manual page, copious documentation in files whose names begin with 00, and a copy of this FAQ in the file 00FAQ (perhaps slightly less recent than this file if you're reading it via a web browser.) Two URLs provide some documentation that appears in the lsof distribution: FAQ: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/FAQ man page: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/lsof_man 1.4 How do I report an lsof bug? If you believe you have discovered a bug in lsof, you can report it via e-mail to <abe@purdue.edu>. Do NOT report lsof bugs to the UNIX dialect vendor. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. Before you send me a bug report, please read the "Bug Reports" section of the 00README file of the lsof distribution. It lists the steps you should take before and when reporting a suspected bug. 1.5 Where can I get the lsof FAQ? This lsof FAQ is available in the file 00FAQ in the lsof distribution and at the URL: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/FAQ 1.5.1 How timely is the on-line FAQ? The on-line FAQ is sometimes too timely. :-) I update it as soon as new information is available. That may include information about support that won't appear in the lsof source distribution until the next revision. If you encounter something like that, please send me e-mail at <abe@purdue.edu>. I may be able to point you at a pre-release distribution that contains the support of interest. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 1.6 Is there a test suite? Yes, as of lsof revision 4.63 there's an automated lsof test suite in the tests/ sub-directory of the lsof top-level directory. More information on using the test suite, what it does, how to use it and how to configure it may be found in the 00TEST file of the lsof distribution. That file also explains where the test suite has been tested. Frequently asked questions about the test suite will be asked and answered here in the FAQ. (See "Test Suite Problems.") After lsof has been configured with the Configure script, lsof can be made and tested with: $ make $ cd tests $ make Under normal conditions -- i.e., unless the lsof tree has been cleaned or purged severely -- all tests or individual tests may be run by: $ cd test $ make or $ <run a single test> (See 00TEST.) 1.7 Is lsof vulnerable to the standard I/O descriptor attack? Lsof revisions 4.63 and above are not vulnerable. Lsof revisions 4.62 and below are vulnerable, but no damage scenarios have so far been demonstrated. The standard I/O descriptor attack is a local programmed assault on setuid and setgid programs that tricks them into opening a sensitive file with write access on a standard descriptor, usually stderr (2), and writing error messages to stderr. If the attacker can control the content of the error message, the attacker may gain elevated privileges. The attack was first described in Pine Internet Advisory PINE-CERT-20020401, available at: http://www.pine.nl/advisories/pine-cert-20020401.txt If you are using an lsof revision below 4.63, you should remove any setuid or setgid permissions you might have given its executable. Then you should upgrade to lsof revision 4.63. 1.8 Can I alter lsof's make(1) behavior? Yes. There are at least two ways to do that. You can put replacements for lsof Makefile strings in your environment. If you specify the -e make option, make will give environment variable values precedence over strings from the Makefile. For example, to change the compiler string CC from the environment, you might do this with the Bourne shell: $ CC=foobar; export CC $ make -e You can also replace lsof Makefile strings in the make command invocation. Here's the previous example done that way: $ make CC=foobar Changing the CFGF, CFGL, and DEBUG strings used in lsof Makefiles, either from the environment or from the make invocation, can significantly alter lsof make(1) behavior. I commonly use DEBUG to change the -O option to -g so I can build an lsof executable for debugging -- e.g., $ make DEBUG=-g (Look for DEBUG in this FAQ for other examples of its use.) Consult the Makefiles to see what CFGL, CFGL, and other lsof Makefile strings contain, and to see what influence their alteration might have on lsof make(1) behavior. 1.9 Is there an lsof license? No. The only restriction on the use or redistribution of lsof is contained in this copyright statement, found in every lsof source file. (The copyright year in or format of the notice may vary slightly.) /* * Copyright 2002 Purdue Research Foundation, West Lafayette, * Indiana 47907. All rights reserved. * * Written by Victor A. Abell * * This software is not subject to any license of the American * Telephone and Telegraph Company or the Regents of the * University of California. * * Permission is granted to anyone to use this software for * any purpose on any computer system, and to alter it and * redistribute it freely, subject to the following * restrictions: * * 1. Neither the authors nor Purdue University are responsible * for any consequences of the use of this software. * * 2. The origin of this software must not be misrepresented, * either by explicit claim or by omission. Credit to the * authors and Purdue University must appear in documentation * and sources. * * 3. Altered versions must be plainly marked as such, and must * not be misrepresented as being the original software. * * 4. This notice may not be removed or altered. */ 1.10 Language locale support 1.10.1 Does lsof support language locales? How do I use the support? Most UNIX dialect versions of lsof support 8 bit language locale characters -- e.g., the ability to print 8 bit characters that have accents and other marks over them. See the answer to the "Does lsof support wide characters in language locales?" question for information on when lsof's language locale support covers characters wider than 8 bits. To see if lsof supports language locales for your dialect, look in the dialect's machine.h header file for the HASSETLOCALE definition. If it is present and not disabled, then lsof has language locale support for the dialect. To enable lsof's language locale support, you must specify in a locale environment variable (e.g., LANG) a language locale known to your system that supports the printing of marked characters -- e.g, en_US. (On some dialects locale(1) may be used to list the known language locales.) Note that LANG=C and LANG=POSIX are NOT language locales that support the printing of marked characters. If the language locale doesn't support the printing of marked characters, lsof's OUTPUT of them follows the rules for non-printable characters described in the OUTPUT section of lsof(8). Consult your dialect's setlocale(3) man page for the names of environment variables other than LANG -- e.g., LC_ALL, LC_TYPE, etc. -- which may be used to define language locales. 1.10.2 Does lsof support wide characters in language locales? When lsof's language locale support is enabled with the HASSETLOCALE definition, for selected dialects lsof will also print wide characters (e.g., from UTF-8) when iswprint(3) reports them to be printable. Wide character support is available when HASWIDECHAR is defined in a dialect's machine.h header file. As of this writing on July 22, 2004, the following dialect versions have wide character support: AIX >= 4.3.2 Apple Darwin >= 7.3.0 FreeBSD >= 5.2 HP-UX >= 11.00 /proc-based Linux NetBSD >= 1.6 SCO OpenServer >= 5.0.6 Solaris >= 2.6 Tru64 UNIX 5.1 1.11 Are any files in the lsof distribution copyrighted? Yes. Most files carry the copyright of the Purdue Research Foundation and may be redistributed under the terms that accompany the copyright notice. Those terms may also be found in the answer to the question, "Is there an lsof license?") A few files carry other copyright notices. Some are BSD notices and they explain the terms under which they are included in the lsof distribution. Those that carry vendor copyright notices have been reproduced in their original or modified forms with permission from the copyright owners. That permission is indicated in the README files that accompany the files. 1.12 Are there other lsof-related resources? There are other resources available, connected to lsof. Among them are FreeBSD and Linux packages whose products use lsof and two particularly interesting resources. The two interesting resources are a Gnome Tool Kit (GTK) GUI for lsof and a Perl wrapper module. The GTK GUI is called Glsof and was developed by Gnele. It can be found at: http://www.sourceforge.net The Perl wrapper module by Marc Beyer can be found at: http://search.cpan.org/dist/Unix-Lsof/ 2.0 Lsof Ports 2.1 What ports exist? The pub/lsof.README file carries the latest port information: AIX 5.[23] and 5.3 FreeBSD 4.9 for x86-based systems FreeBSD 7.[012] and 8.0 for AMD64-based systems Linux 2.1.72 and above for x86-based systems Solaris 9 and 10 In the above list the only UNIX dialects present are ones for which I test the current lsof revision. Lsof may still support unlisted dialect versions -- e.g., HP-UX 10.20, Solaris 7, etc. -- but I don't have access to systems where I could test lsof on them, so I can't claim lsof works on them. If your dialect isn't in the list, you should try building lsof on it anyway. Lsof version 4 predecessors, versions 2 and 3, may support older version of some dialects. Contact me via e-mail at <abe@purdue.edu> if you're interested in their distributions. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 2.2 What about a new port? The 00PORTING file in the distribution gives hints on doing a port. I will consider doing a port in exchange for permanent access to a test host. I require permanent access so I can test new lsof revisions, because I will not offer distributions of dialect ports I cannot upgrade and test. 2.2.1 User-contributed Ports Sometimes I receive contributions of ports of lsof to systems where I can't test future revisions of lsof. Hence, I don't incorporate these contributions into my lsof distribution. However, I do make descriptions of these contributions available. You can find them in the 00INDEX and README files at: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/contrib Consult the 00INDEX file in the contrib/ directory for a list of the available contributions and consult README there for information on how to obtain them. 2.3 Why isn't there an AT&T SVR4 port? I haven't produced an AT&T SVR4 port because I haven't seen a UNIX dialect that is strictly limited to the AT&T System V, Release 4 source code. Every one I have seen is a derivative with vendor additions. The vendor additions are significant to lsof because they affect the internal kernel structures with which lsof does business. While some vendor derivatives of SVR4 are similar, each one I have encounted so far has been different enough from its siblings to require special source code. If you're interested in an SVR4 version of lsof, here are some existing ports you might consider: DC/OSx (This obsolete port is only available upon special request.) Reliant UNIX (This obsolete port is only available upon special request.) SCO|Caldera UnixWare (This is the most likely choice.) Solaris 2.4 Why isn't there an SGI IRIX port? Lsof support for IRIX was terminated at lsof revision 4.36, because it had become increasingly difficult for me to obtain information on the IRIX kernel structures lsof needs to access. At IRIX 6.5 I decided the obstacles were too large for me to overcome, and I stopped supporting lsof on IRIX. I have sources to the last revision of lsof (4.36) for IRIX, but that version of lsof does not work on IRIX 6.5 and is vulnerable to the standard I/O descriptor attack. (See the "Is lsof vulnerable to the standard I/O descriptor attack?" Q&A for more information.) Contact me to discuss obtaining those sources. If you wish to pursue the issue, don't contact me, contact SGI. This case was opened with SGI on the subject: Case ID: 0982584 Category: Unix Priority: 30-Moderate Impact Problem Summary: kernel structure header files needed for continued lsof support Problem Description: Email In 07/17/98 19:09:23 2.5 Why does lsof's Configure script report "WARNING: unsupported dialect or version"? Lsof's Configure script issues this message when it encounters a dialect or its version that lsof once supported, but no longer does. Usually I drop support for a dialect or version when I can no longer test lsof on it. However, it's worth trying to compile and use lsof. Be sure to run the test suite. (See the answer to the "Is there a test suite? question for information on the test suite.) If you have problems with an unsupported dialect or version, contact me via e-mail at <abe@purdue.edu> and I may be able to help. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 3.0 Lsof Problems 3.1 Configuration Problems 3.1.1 Why can't Configure determine the UNIX dialect version? The lsof Configure script uses UNIX shell commands, often in a command pipeline, to determine the UNIX dialect version. (Consult the dialect stanza in Configure to determine which commands are used.) If Configure can't determine the dialect version, probably one of the commands is not behaving as Configure expects. Symptoms of the failure include Configure warning messages and incorrect version definitions in the Makefile CFLAGS. If you suspect that the lsof Configure script is failing to determine the dialect version correctly, try running the commands from Configure stanza one at a time. That will usually reveal the source of the problem. Be particularly mindful that the PATH environment variable can cause commands to be executed from non-standard directories. If you can't determine the source of the problem, there is a work-around. You can supply the UNIX dialect version in the LSOF_VSTR environment variable. Use Configure as a guide to forming what it expects in LSOF_VSTR. There is also some information on LSOF_VSTR in the 00XCONFIG documentation file of the lsof distribution. 3.2 Compilation Problems 3.2.1 Why does the compiler complain about missing header files? When you use make to build lsof, the compiler may complain that it can't find header files -- e.g., $ make (cd lib; make DEBUG="-O" CFGF="-DAIXA=0 -DAIXV=4330 \ -DLSOF_VSTR=\"4.3.3.0\"") gcc -DAIXA=0 -DAIXV=4330 -DLSOF_VSTR="4.3.3.0" -O \ -c ckkv.c In file included from ckkv.c:33: ../machine.h:70: \ sys/types.h: A file or directory in the path name \ does not exist. \ That type of complaint doesn't represent an lsof problem. It represents a problem with a missing system header file that probably should be found in /usr/include or in the system source tree. As a first step try using find(1) to locate the problem header file. If it's a system header file and can't be found, here are some possible causes: 1. The file set, RPM or package containing the header files has not been installed. instructions for doing that are specific to the UNIX dialect and beyond the scope of this document. 2. If the compiler is gcc, the private gcc header files: * May not have been installed; * May have been installed incorrectly; * May not have been updated properly after the last compiler or system update; * Ones from a previous installation may not have been removed. A path leading to the gcc private header files can be found with `gcc -v`. Consult the gcc documentation for instructions on proper installation of the private gcc header files. 3. On some dialects -- e.g., FreeBSD, NetBSD, OpenBSD -- lsof may need to use header files that are located in the system source tree -- /sys or /usr/src/sys, for example. Make sure the system source tree has been installed. 3.2.2 Why does gcc complain about the contents of header files distributed by the system's vendor? When you use make to build lsof and gcc to compile it, gcc may complain that it finds errors in system header files -- e.g., $ make (cd lib; make DEBUG="-O" CFGF="-Dsolaris=80000 \ -DHASPR_GWINDOWS -m64 -DHASIPv6 -DHAS_VSOCK \ -DLSOF_VSTR=\"5.8\"") gcc -Dsolaris=80000 -DHASPR_GWINDOWS -m64 -DHASIPv6 \ -DHAS_VSOCK -DLSOF_VSTR="5.8" -O -c dvch.c In file included from /usr/include/sys/proc.h:31, \ from /homes/abe/gnu/gcc-3.2.1/lib/gcc-lib/sparcv9-sun-solaris2/ \ 3.2.1/include/sys/user.h:267, from /usr/include/kvm.h:13, \ from ../dlsof.h:53, from ../lsof.h:172, from dvch.c:43: \ /homes/abe/gnu/gcc-3.2.1/lib/gcc-lib/sparcv9-sun-solaris2/\ 3.2.1/include/sys/task.h:59: parse error before "uint_t" Errors like the above are most likely not problems in the system's header files, but in the private copies of them that were created when gcc was made or installed. Note the presense of ".../gcc-3.2.1/lib/gcc-lib/sparcv9-sun-solaris2/3.2.1/include/..." in the paths for user.h and task.h. It indicates both header files are gcc-specific. To solve errors like this requires comparing the header files in the vendor's /usr/include tree to the gcc-specific ones in gcc's private gcc-lib/.../include tree. It may be necessary to regenerate gcc-specific header files, correct them or remove them. See the gcc distribution for the appropriate tools. A possible temporary work-around is to direct gcc to use the vendor's header files instead of its temporary ones by declaring -I/usr/include in the compilation flags. 3.2.3 Other header file problems Don't overlook any vendor tools that might validate the vendor header files installed on the system -- e.g., the Solaris pkgchk tool can be used to check the header files that were installed from the SUNWhea package. For other header file problems contact me at <abe@purdue.edu>. Please follow the reporting guidelines in the "How do I report an lsof bug?" section of this FAQ. 3.3 Why doesn't lsof report full path names? Lsof reports the full path name when it is specified as a search argument for open files that match the argument. However, if the argument is a file system mounted-on directory, and lsof finds additional path name components from the kernel name cache, it will report them. Lsof reports path name for file system types that have path name lookup features -- e.g., some versions of AdvFS for Digital and Tru64 UNIX. The Linux /proc-based lsof reports full path names, because the Linux /proc file system provides them. Lsof on recent builds of Solaris 10 also report full path names, because those Solaris kernels record the full path name in the vnode structure. Otherwise, lsof uses the kernel name cache, where it exists and can be accessed, and reports some or all path name components (e.g., the sys and proc.h components of /usr/include/sys/proc.h) for these dialects: Apple Darwin DC/OSx FreeBSD HP-UX, /dev/kmem and PSTAT based Linux, /dev/kmem-based NetBSD NEXTSTEP OpenBSD OPENSTEP Reliant UNIX SCO OpenServer SCO|Caldera UnixWare Solaris 2.x, 7, 8 and 9 (except for some VxFS versions; see the "Why doesn't Solaris lsof report VxFS path name components?" section for more information) Solaris 10 (early builds) Tru64 UNIX As far as I can determine, AFS path lookups don't share in kernel name cache operations, so lsof can't identify open AFS path name components. Apparently Solaris VxFS versions 4 and above don't share in kernel name cache operations, either, so lsof can't display path name components for those open files. Since the size of the kernel name cache is limited and the cache is in constant flux, it does not always contain the names of all components in an open file's path; sometimes it contains none of them. Lsof reports the file system directory name and whatever components of the file's path it finds in the cache, starting with the last component and working backwards through the directories that contain it. If lsof finds no path components, lsof reports the file system device name instead. When lsof does report some path components in the NAME column, it prefixes them with the file system directory name, followed by " -- ", followed by the components -- e.g., /usr -- sys/path.h for /usr/include/sys/path.h. The " -- " is omitted when lsof finds all the path name components of a file's name. The PSTAT-based HP-UX lsof relies on kernel name cache contents, too, even though its information comes to lsof via pstat() function calls. Consequently, PSTAT-based HP-UX lsof won't always report full paths, but may use the " -- " partial path name notation, or may occasionally report no path name at all but just the file system mounted-on directory and device names. Lsof can't obtain path name components from the kernel name caches of the following dialects: AIX Only the Linux kernel records full path names in the structures it maintains about open files; instead, most kernels convert path names to device and node number doublets and use them for subsequent file references once files have been opened. To convert the device and node number doublet into a complete path name, lsof would have to start at the root node (root directory) of the file system on which the node resides, and search every branch for the node, building possible path names along the way. That would be a time consuming operation and require access to the raw disk device (usually implying setuid-root permission). If the prospect of all that local disk activity doesn't concern you, think about the cost when the device is NFS-mounted. Try using the file system mount point and node number lsof reports as parameters to find -- e.g., $ find <mount_point> -inum <node_number> -print and you may get an appreciation of what a file system directory tree search would cost. 3.3.1 Why do lsof -r reports show different path names? When you run lsof with its repeat (``-r'') option, you may notice that the extent to which it reports path names for the same files may vary from cycle to cycle. That happens because other processes are making kernel calls affecting the cache and causing entries to be removed from and added to it. 3.3.2 Why does lsof report the wrong path names? Under some circumstances lsof may report an incorrect path name component, especially for files in a rapidly changing directory like /tmp. In a rapidly changing directory, like /tmp, if the kernel doesn't clear the cache entry when it removes a file, a new file may be given the same keys and lead lsof to believe that the old cache entry with the same keys belongs to the new file. Lsof tries to avoid this error by purging duplicate entries from its copy of the kernel name cache when they have the same device and inode number, but different names. This error is less likely to occur in UNIX dialects where the keys to the name cache are node address and possibly a capability ID. The Apple Darwin, Digital UNIX, FreeBSD, HP-UX, NEXTSTEP, OPENSTEP, Solaris, Tru64 UNIX, and UnixWare dialects use node address. Apple Darwin, FreeBSD, NetBSD, OpenBSD, Tru64 UNIX, and also use a capability ID to further identify name cache entries. 3.3.3 Why doesn't lsof report path names for unlinked (rm'd) files? When lsof gets path name components from the kernel's name cache, it does not report the path names of a file that has been unlinked from its parent directory -- e.g., deleted via rm, or the unlink() system call -- even when some process may still hold the file open; lsof reports only the file system's mounted-on directory and device. That's because path name components are removed from the kernel name cache when the file is unlinked. Unlinked open files are sometimes used by applications for temporary, but invisible storage (i.e., ls won't show them, and no other process can open them.) However, they may occasionally consume disk space to excess and cause concern for a system administrator, who will be unable to locate them with find, ls, du, or other tools that rely on finding files by examining the directory tree. By using lsof's +L option you can see the link count of open files -- in the NLINK column. An unlinked file will have an NLINK value of zero. By using the option +L1 you can tell lsof to display only files whose link count is less than one (i.e., zero). There are some UNIX dialect-specific exceptions to lsof's inability to report unlinked path names. They are described in the answer to the "When will lsof report path names for deleted files?" question. 3.3.4 Why doesn't lsof report the "correct" hard linked file path name? When lsof reports a rightmost path name component for a file with hard links, the component may come from the kernel's name cache. Since the key which connects an open file to the kernel name cache may be the same for each differently named hard link, lsof may report only one name for all open hard-linked files. Sometimes that will be "correct" in the eye of the beholder; sometimes it will not. Remember, the file identification keys significant to the kernel are the device and node numbers, and they're the same for all the hard linked names. 3.3.5 When will lsof report path names for deleted files? Lsof will report path names for deleted files for two dialects: Linux and later builds of Solaris 10. Deleted Linux path names are reported by default and have "(deleted)" at their ends. The display of Solaris 10 deleted path names may be selected with the -X option. When selected they are also reported with "(deleted)" at their ends. 3.4 Why is lsof so slow? Lsof may appear to be slow if network address to host name resolution is slow. This can happen, for example, when the name server is unreachable, or when a Solaris PPP cache daemon is malfunctioning. To see if name lookup is causing lsof to be slow, turn it off with the ``-n'' option. Port service name lookup or portmap registration lookup may also be causes of slow-down. To suppress port service name lookup, specify the ``-P'' option. Lsof doesn't usually make direct portmap calls -- only when +M is specified, or when HASPMAPENABLED is defined during lsof construction. (The lsof help panel, produced with `lsof -h` will display the default portmap registration reporting state.) The quickest first step in checking if lsof is slow because of the portmapper is to use lsof's ``-M'' option. Lsof may be slow if UID to login name lookups are slow. Suppress them with ``-l''. On dialects where lsof uses the kernel name cache, try disabling its use with ``-C''. (You can tell if lsof uses the kernel name cache by looking for ``-C'' in lsof's ``-h'' output.) Of course, disabling kernel name cache use will mean that lsof won't report full or partial path names, just file system and character device names. If you're just interested in the open files of one process, try using the ``-p <Process-ID>'' option to limit lsof to that process. (The ``-p'' option may also be followed with a list of Process-IDs.) If you're interested in including or excluding certain commands, try lsof's "-c[^]cmd" option. If you're interested in certain Internet TCP and UDP states (e.g, ESTABLISHED) or in excluding some (e.g., CLOSE_WAIT), try lsof's "-s p:s" option. More information on it may be found in the answer to the "How are protocol state name exclusion and inclusion used?" question. Your UNIX dialect may not support "-s p:s" and its associated performance improvments to Internet-only file processing. You can find more information on those topics in the answer to the "Why doesn't my dialect support state name exclusion and inclusion?" question. Older AIX lsof may be slow to start because of its oslevel identity comparison. (Newer AIX lsof uses uname(2).) See the "Why does AIX lsof start so slowly?" and "Why does lsof warn "compiled for x ... y; this is z.?" sections for more information. 3.5 Why doesn't lsof's setgid or setuid permission work? If you install lsof on an NFS file system that has been mounted with the nosuid option, lsof may not be able to use the setgid or setuid permission you give it, complaining it can't open the kernel memory device -- e.g., /dev/kmem. The only solution is to install lsof on a file system that doesn't inhibit setgid or setuid permission. 3.6 Does lsof have security problems? I don't think so. However, lsof does usually start with setgid permission, and sometimes with setuid-root permission. Any program that has setgid or setuid-root permission, should always be regarded with suspicion. Lsof drops setgid power, holding it only while it opens access to kernel memory devices (e.g., /dev/kmem, /dev/mem, /dev/swap). That allows lsof to bypass the weaker security of access(2) in favor of the stronger checks the kernel makes when it examines the right of the lsof process to open files declared with -k and -m. Lsof also restricts some device cache file naming options when it senses the process has setuid-root power. On a few dialects lsof requires setuid-root permission during its full execution in order to access files in the /proc file system. These dialects include: DC/OSx 1.1 for Pyramid systems Reliant UNIX 5.4[34] for Pyramid systems When lsof runs with setuid-root permission it severely restricts all file accesses it might be asked to make with its options. The device cache file (typically .lsof_hostname in the home directory of the real user ID that executes lsof) has 0600 modes. (The suffix, hostname, is the first component of the host's name returned by gethostname(2).) However, even when lsof runs setuid-root, it makes sure the file's ownerships are changed to that of the real user and group. In addition, lsof checks the file carefully before using it (See the question "How do I disable the device cache file feature or alter it's behavior?" for a description of the checks.); discards the file if it fails the scrutiny; complains about the condition of the file; then rebuilds the file. See the 00DCACHE file of the lsof distribution for more information about device cache file handling and the risks associated with the file. 3.7 Will lsof show remote hosts using files via NFS? No. Remember, lsof displays open files for the processes of the host on which it runs. If the host on which lsof is running is an NFS server, the remote NFS client processes that are accessing files on the server leave no process records on the server for lsof to examine. 3.8 Why doesn't lsof report locks held on NFS files? Generally lock information held by local processes on remote NFS files is not recorded by the UNIX dialect kernel. Hence, lsof can't report it. One exception is some patch levels of Solaris 2.3, and all versions of Solaris 2.4 and above. Lsof for those dialects does report on locks held by local processes on remotely mounted NFS files. 3.8.1 Why does lsof report a one byte lock on byte zero as a full file lock? When a process has a lock of length one, starting at byte zero, lsof can't distinguish it from a full file lock. That's because most UNIX dialects represent both locks the same way in their file lock (flock or eflock) structures. 3.9 Why does lsof report different values for open files on the same file system (the automounter phenomenon)? On UNIX dialects where file systems may be mounted by an automounter with the ``direct'' type, lsof may sometimes report difference DEVICE, SIZE/OFF, INODE and NAME values when asked to report files open on the file system. This happens because some files open on the file system -- e.g., the current directory of a shell that changed its directory to the file system as the file system's first reference -- may be characterized in the kernel with temporary automounter node information. The cd doesn't cause the file system to be mounted. A subsequent reference to the file system -- e.g., an ls of any place in it -- will cause the file system to be mounted. Processes with files open to the mounted file system are characterized in the kernel with data that reflects the mounted file system's parameters. Unfortunately some kernels (e.g., some versions of Solaris 2.x) don't revisit the process that did only a change-directory for the purpose of updating the data associated with the open directory file. The file continues to be characterized with temporary automounter information until it does another directory change, even a trivial ``cd .''. Lsof will report on both reference types, when supplied the file system name as an argument, but the data lsof reports will reflect what it finds in the kernel. For the different types lsof will display different data, including different major and minor device numbers in the DEVICE column, different lengths in the SIZE/OFF column, different node numbers in the INODE column, and slightly different file system names in the NAME column. In contrast, fuser, where available, can only report on one reference type when supplied the file system name as an argument. Usually it will report on the one that is associated with the mounted file system information. If the only reference type is the temporary automounter one, fuser will often be silent about it. 3.10 Why don't lsof and netstat output match? Lsof and netstat output don't match because lsof reports the network information it finds in open file system objects -- e.g., socket files -- while netstat often gets its information from separate kernel tables. The information available to netstat may describe network activities never or no longer associated with open files, but necessary for proper network state machine operation. For example, a TCP connection in the FIN_WAIT_[12] state may no longer have an associated open file, because the connection has been closed at the application layer and is now being closed at the TCP/IP protocol layer. 3.10.1 Why can't lsof find accesses to some TCP and UDP ports? Lsof stands for LiSt Open Files. If there is no open file connected to a TCP or UDP port, lsof won't find it. That's the most common reason why lsof doesn't find a port netstat might report open. One reason I've found on some UNIX dialects is that their kernels set aside TCP and UDP ports for communicating with support activities, running in application layer servers -- the automounter daemons, and the NFS biod and nfsd daemons are examples. Netstat may report the ports are in use, but lsof doesn't. Another reason is that netstat may also be able to report a port is open on a particular dialect, because it uses a source of data different from what lsof uses -- e.g., netstat might examine kernel tables or use streams messages to MIB2, while lsof relies on the information it finds in open file structures and their descendants. Sometimes it's possible to search the data netstat and lsof use. For example, on Linux /proc/tcp and /proc/udp can be examined. There might an entry there for a particular protocol and port, but if the line on which the port appears doesn't have an inode number that matches an inode number of an open file, lsof won't be able to identify the process using the port. This is a tough question to which there is no easy answer. 3.11 Why does lsof update the device cache file? At the end of the lsof output you may see the message: lsof: WARNING: /Homes/abe/.lsof_vic was updated. In this message /Homes/abe/.lsof_vic is the path to the private device cache file for login abe. (See 00DCACHE.) Lsof issues this message when it finds it necessary to recheck the system device directory (e.g., /dev or /devices) and rebuild the device cache file during the open file scan. Lsof may need to do these things it finds that a device directory node has changed, or if it cannot find a device in the cache. 3.12 Why doesn't lsof report state for UDP socket files? Lsof reports UDP TPI connection state -- TS_IDLE (Idle), TS_BOUND (Bound), etc. -- for some, but not all dialects. TPI state is stream-based TCP/IP information that isn't available in many dialects. A fairly weak general rule is if netstat(1) reports UDP TPI state, lsof may be able to report it, too. But don't be surprised if lsof fails to report UDP TPI state for your dialect. Other factors influence lsof's ability to report UDP TPI state, including the availability of state number data in kernel structures, and state number to state name conversion data. 3.13 I am editing a file with vi; why doesn't lsof find the file? Classic implementations of vi usually don't keep open the file being edited. (Newer ones may do so in order to maintain an advisory lock.) Instead classic vi opens the file, makes a temporary copy (usually in /tmp or /usr/tmp), and does its work in that file. When you save the file being edited from a classic vi implementation, it reopens and rewrites the file. During a classic vi session, except for the brief periods when vi is reading or rewriting the file, lsof won't find an open reference to the file from the vi process, because there is none. 3.14 Why doesn't lsof report TCP/TPI window and queue sizes for my dialect? Lsof only reports TCP/TPI window sizes for Solaris, because only its netstat reports them. The intent of providing TCP/TPI information in lsof NAME column output is to make it easier to match netstat output to lsof output. In general lsof only reports queue sizes for both TCP and UDP (TPI) connections on BSD-derived UNIX dialects, where both sets of values appear in kernel socket queue structures. SYSV-derived UNIX dialects whose TCP/IP implementations are based on streams generally provide only TCP queue sizes, not UDP (TPI) ones. While you may find that netstat on some SYSV-derived UNIX dialects with streams TCP/IP may report UDP (TPI) queue sizes, you will probably also find that the sizes are always zero -- netstat supplies a constant zero for UDP (TPI) queue sizes to make its headers align the same for TCP and UDP (TPI) connections. Solaris seems to get it right -- i.e., its netstat does not report UDP (TPI) queue sizes. When in doubt, I chose to avoid reporting UDP (TPI) queue sizes for UNIX dialects whose netstat-reported values I knew to be a constant zero or whose origin I couldn't determine. OSR is a dialect in this category. 3.14.1 Why doesn't lsof report socket options, socket states, and TCP flags and values for my dialect? The lsof -T argument, 'f', that selects the reporting of socket options, socket states and TCP flags was implemented at lsof revision 4.71 for the following UNIX dialects, providing the indicated information: AIX 4.3.2 and 5.1 and above All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. Apple Darwin 7.2 and above All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. Digital UNIX and Tru64 UNIX 4.0 All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. FreeBSD 4.9 and above All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. HP-UX 11.00 (/dev/kmem-based lsof) All socket options and values are reported. No socket states are reported. Only the TF_NODELAY TCP flag and the TF_MSS value are reported. HP-UX 11.11 and iiiv2 (PSTAT-based lsof) All socket options and values, and socket states are reported. No TCP flags or values are reported. Linux No socket options and values, socket states, or TCP flags and values are reported. The support for "-Tf" could not be added to Linux, because socket options, socket states, and TCP flags and values are not available via the /proc file system. NetBSD 1.6G and above All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. OpenBSD 3.4 and above All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. OPENSTEP 4.2 All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. OpenUNIX 8 All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. SCO OpenServer Release 5.0.6 All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. Solaris 2.6, 8 and above The socket option display is limited to BROADCAST, DEBUG, DGRAM_ERRIND, DONTROUTE and OOBINLINE. Socket values are limited to KEEPALIVE and LINGER. No socket states are reported. The TCP DELACK, NODELAY and SENTFIN flags are reported. The TCP MSS value is reported. UnixWare 7.1.[134] All socket options and values, socket states, and TCP flags and values described in lsof(8) are reported. 3.14.2 Why doesn't lsof report the partial listen queue connection count for my dialect? The reporting of partial listen queue connections was added to -Tf processing at lsof revision 4.76. Currently it is reported for these dialects: AIX 4.3.2 This dialect is no longer supported, so no attempt was made to add partial listen queue length support for it. AIX 5.1 and above Partial listen queue information is available. Apple Darwin 7.2 and above Partial listen queue information is available. Digital UNIX 4.0 This dialect is no longer supported, so no attempt was made to add partial listen queue length support for it. FreeBSD 4.9 and above Partial listen queue information is available. HP-UX 11.00 (/dev/kmem-based lsof) No partial listen queue information is available. HP-UX 11.11 and iiiv2 (PSTAT-based lsof) No partial listen queue information is available. Linux No partial listen queue information is available. NetBSD 1.6G and above Partial listen queue information is available. OpenBSD 3.4 and above Partial listen queue information is available. OPENSTEP 4.2 Partial listen queue information is available. OpenUNIX 8 This dialect is no longer supported, so no attempt was made to add partial listen queue length support for it. SCO OpenServer Release 5.0.6 No partial listen queue information is available. Solaris 2.6, 8 and above Partial listen queue information is available. Tru64 UNIX 5.0 This dialect is no longer supported, so no attempt was made to add partial listen queue length support for it. Tru64 UNIX 5.1 Partial listen queue information is available. UnixWare 7.1.[134] Partial listen queue information is available. 3.15 What does "no more information" in the NAME column mean? When lsof can find no successor structures -- a gnode, inode, socket, or vnode -- connected to the file structure of an open descriptor of a process, it reports "no more information" in the NAME column. The TYPE, DEVICE, SIZE/OFF, and INODE columns will be blank. Because the file structure is supposed to contain a pointer to the next structure of a file's processing support, if the pointer is NUL, lsof can go no further. Some UNIX dialects have file structures for system processes -- e.g., the sched process -- that have no successor structure pointers. The "no more information" NAME will commonly appear for these processes in lsof output. It may also be the case that lsof has read the file structure while it is being assembled and before a successor structure pointer value has been set. The "no more information" NAME will again result. Unless lsof output is filled with "no more information" NAME column messages, the appearance of a few should be no cause for alarm. 3.16 Why doesn't lsof find a process that ps finds? If lsof fails to display open files for a process that ps indicates exists, there may be several reasons for the difference. The process may be a "zombie" for which ps displays the "(defunct)" state. In that case, the process has exited and has no open file information lsof can display. It does still have a process structure, sufficient for the needs of ps. Another possible explanation is that kernel tables and structures may have been changing when lsof looked for the process, making lsof unable to find all relevant process structures. Try repeating the lsof request. 3.17 Why doesn't -V report a search failure? The usual reason that -V won't report a search failure is that lsof located the search item, but was prevented from listing it by an option that doesn't participate in search failure reporting. For example, this lsof invocation: $ lsof -V -i TCP@foobar -a -d 999 won't report it can't find the Internet address TCP@foobar, even if there is an open file connected to that address, unless the open file also has a file descriptor number of 999 (the ``-a -d 999'' options). Compile-time options can also affect -V results in much the same way. For example, if HASSECURITY and HASNOSOCKSECURITY are defined at compile time, this lsof invocation, run by a non-root user: $ lsof -V -c inetd won't report that it can't find the inetd command, even if there is a process running the inetd command, because the HASSECURITY and HASNOSOCKSECURITY options prevent the listing of all but the socket files of another user, and no socket file selector (e.g., "-i") was specified. 3.18 Portmap problems 3.18.1 Why isn't a name displayed for the portmap registration? When portmap registration reporting is enabled, any time there is a registration for a local TCP or UDP port, lsof displays it in square brackets, following the port number or service name -- e.g., ``:1234[name]'' or ``:name[100083]''. The TCP or UDP port number or service number (what follows the `:') is displayed under the control of the lsof -P option. The registration identity is held by the portmapper and may be a name or a number, depending on how the registration's owner declared it. Lsof reports what the port map holds and cannot derive a registration name from a registration number. Lsof can be compiled with registration reporting enabled or disabled by default, under the control of the HASPMAPENABLED #define (usually in machine.h). The lsof help panel (`lsof -h`) will show the default. Lsof is distributed with reporting disabled by default. 3.18.2 How can I display only portmap registrations? Lsof doesn't have an option that will display only TCP or UDP ports with portmap registrations. The +M option only enables the reporting of registration information when Internet socket files are displayed; +M doesn't select the displaying of Internet socket files -- the -i option does that. This simple lsof pipe to grep will do the job: $ lsof -i +M | grep "\[" This works because -i selects Internet socket files, +M enables portmap registration reporting, and only output lines with opening square brackets will have registrations. When portmap registration reporting is enabled by default, because the lsof builder constructed it that way, +M is not necessary. (The lsof help panel, produced with `lsof -h` will display the default portmapper registration reporting state.) However, specifying +M when reporting is already enabled is acceptable, as is specifying -M when reporting is already disabled. Digression: lsof will accept `+' or `-' as a prefix to most options. (That isn't documented in the man page or help panel to reduce confusion and complexity.) The -i option is as acceptable as +i, so the above example could be written a little more tersely as: $ lsof +Mi | grep "\[" But be careful to use the ``Mi'' ordering, since ``iM'' implies M is an address argument to `i'. 3.18.3 Why doesn't lsof report portmap registrations for some ports? Lsof reports portmap registrations for local TCP and UDP ports only. It identifies local ports this way: * The port appears in the local address section of the kernel structure that contains it. * The port appears in the foreign address section of a kernel structure whose local and foreign Internet addresses are the same. * The port appears in the foreign address section of a kernel address structure whose Internet address is INADDR_LOOPBACK (127.0.0.1). Following these rules, lsof ignores foreign portmapped ports. That's done for reasons of efficiency and possible security prohibitions. Contacting all remote portmappers could take a long time and be blocked by network difficulties (i.e., be inefficient). Many firewalls block portmapper access for security reasons. Lsof may occasionally ignore portmap registration information for a legitimate local port by virtue of its local port rules. This can happen when a port appears in the foreign part of its kernel structure and the local and foreign Internet addresses don't match (perhaps because they're on different interfaces), and the foreign Internet address isn't INADDR_LOOPBACK (127.0.0.1). 3.19 Why is `lsof | wc` bigger than my system's open file limit? There is a strong temptation to count open files by piping lsof output to wc. If your purpose is to compare the number you get to some Unix system parameter that defines the number of open files your system can have, resist the temptation. One reason is that lsof reports a number of "files" that don't occupy Unix file table space -- current working directories, root directories, jail directories, text files, library files, memory mapped files are some. Another reason is that lsof can report a file shared by more than one process that itself occupies only one file table slot. If you want to know the number of open files that occupy file table slots, use the +ff option and process the lsof output's FILE_ADDR column information with standard Unix tools like cut, grep, sed, and sort. You might also consider using use lsof's field output with +ff, selecting the file struct address with -FF, and processing the output with an AWK or Perl script. See the list_fields.awk, list_fields.perl, and shared.perl5 scripts in the scripts/ subdirectory of the lsof distribution for hints on file struct post-processing filters. 3.20 Why doesn't lsof report file offset (position)? Lsof won't report a file offset (position) value if the -s option has been specified, or if the dialect doesn't support the displaying of file offset (position). That lsof is reporting only file size is indicated by the fact that the appropriate column header says SIZE instead of SIZE/OFF. If lsof doesn't support the displaying of file offset (position) -- e.g., for Linux /proc-based lsof -- the -h or -? output panel won't list the -o option. Sometimes the availability of file offset information depends on the dialect's kernel. This is particularly true for socket file offsets. Maintenance of offsets for pseudo-terminal devices varies by UNIX dialect and is related to how the dialect kernel implements pseudo-terminal support. Kernels like AIX, for example, that short-circuit the transfer of data between socket and pseudo devices to reduce TCP/IP daemon interrupt rates won't advance offsets in the TCP/IP daemon socket files. Instead they will advance offsets in the open standard I/O files of the shell child precess where the pseudo-terminal devices are used. When in doubt about the behavior of lsof in reporting file offset information, do some carefully measured experiments, consult the lsof sources, or contact me at <abe@purdue.edu> to discuss the matter. Please follow the reporting guidelines in the "How do I report an lsof bug?" section of this FAQ. 3.20.1 What does lsof report for size when the file doesn't really have one? When a file has no true size -- e.g., it's a socket, a FIFO, or a pipe -- lsof tries to report the information it finds in the kernel that describes the contents of associated kernel buffers. Thus, for example, size for most TCP/IP files is socket buffer size. The size of the socket read buffer is reported for read-only files; the size of the write buffer for write-only files; and the sum of the buffers sizes for read-write files. 3.21 Problems with path name arguments 3.21.1 How do I ask lsof to search a file system? You can ask lsof to search for all open files on a file system by specifying its mounted path name as an lsof argument -- e.g., $ lsof / Output of the mount command will show file system mounted path names. It will also show the mounted-on device path for the file system. If the mounted-on device is a block device (the permission field in output of `ls -l <device>` starts with a `b/), you can specify it's name, too -- e.g., $ lsof /dev/sd0a If the mounted-on device isn't a block device -- for example, some UNIX dialects call a CD-ROM device a character device (ls output starts with a `c') -- you can force lsof to assume that the specified device names a file system with the +f option -- e.g., $ lsof +f -- /dev/sd0a (Note: you must use ``--'' after +f or -f if a file name follows immediately, because +f and -f can be followed by characters that specify flag output selections.) When you use +f and lsof can't match the device to a file system, lsof will issue a complaint. The +f option may be used in some dialects to ask lsof to search for an NFS file system by its server name and server mount point. If the mount application reports an NFS file system mounted-on value that way, then this sample lsof request should work. $ lsof +f -- fleet:/home/fleet/u5 Finally, you can use -f if you don't want a mounted file system path name to be considered a request to report all open files on the file system. This is useful when you want to know if anyone is using the file system's mounted path name. This example directs lsof to report on open access to the `/' directory, including when it's being used as a current working or root directory. $ lsof -f -- / The lsof -f option performs the same function as -f does in some fuser implementations. However, since the lsof -c option was chosen for another purpose before the `f' option was added to lsof, +f was selected as the analogue to the fuser -c option. (Sorry for the potential confusion.) 3.21.2 Why doesn't lsof find all the open files in a file system? Lsof may not find all the open files in a file system for several reasons. First, some processes with files open on the file system may have been changing status when lsof examined the process table, and lsof "missed" them. Remember, the kernel changes much faster than lsof can respond to the changes. Second, be sure you have specified the file system correctly. Perhaps you specified a file instead. You can use lsof's -V option to have lsof report in detail on what it couldn't find. Make sure the report for the file system you specified says "file system." Here's some -V output: $ /lsof -V /tmp ./lsof.h ./lsof COMMAND PID USER FD TYPE DEVICE SIZE/OFF INODE NAME lsof 2688 abe txt VREG 18,1,7 1428583 226641 ./lsof lsof 2689 abe txt VREG 18,1,7 1428583 226641 ./lsof lsof: no file use located: ./lsof.h You can also use lsof's +f option to force it to consider a path name as a file system. If lsof can't find a file system by the specified name, it will issue a complaint -- e.g., $ lsof +f -- /usr lsof: not a file system: /usr (/usr is a directory in the / file system.) 3.21.3 Why does the lsof exit code report it didn't find open files when some files were listed? Sometimes lsof will list some open files, yet return a non-zero exit code, suggesting it hasn't found all the specified files. The first thing you should when you suspect lsof is incorrect is to repeat the request, adding the -V option. In the resulting report you may find that your file system specification really wasn't a file system specification, just a file specification. Finally, if you specify two files or two file systems twice, lsof will credit all matches to the first of the two and believe that there were no matches for the second. It's possible to specify a single file system twice with different path names by using both its mounted directory path name and mounted-one device name. $ lsof +f -V spcuna:/sysprog /sysprog COMMAND PID USER FD TYPE DEVICE SIZE/OFF INODE NAME ksh 11092 abe cwd VDIR 39,0,1 1536 226562 /sysprog (spcuna:/sysprog) ... lsof: no file system use located: spcuna:/sysprog All matches were credited to /sysprog; none to spcuna:/sysprog. 3.21.4 Why won't lsof find all the open files in a directory? When you give lsof a simple directory path name argument (not a file system mounted-on name), you are asking it to search for processes that have the directory open as a file, or as a process-specific directory -- e.g., root or current working directory. If you want to list instances of open files inside the directory, you need to specify the individual path names of those files, or use the lsof +D and +d options. See the answer to the question "Why are the +D and +d options so slow?" before you use +D or +d casually. See the answer to the question "Why do the +D and +d options produce warning messages?" for an explanation of some process authority limitations of +D and +d. 3.21.5 Why are the +D and +d options so slow? The +D and +d options cause lsof to build a path name search list for a specified directory. +D causes lsof to descend the directory to its furthest subdirectory, while +d restricts it to the top level. In both cases, the specified directory itself is included in the search list. In both symbolic links are ignored. Building such a search list can take considerable time, especially when the specified directory contains many files and subdirectories -- lsof must call the system readlink() and stat() functions for each file and directory. Storing the search list can cause lsof to use more than its normal amount of dynamic memory -- each file recorded in the search list consumes dynamic memory for its path name, characteristics, and search linkages. Using the list means lsof must search it for every open file in the system. Building the search list for a directory specified on some file systems can be slow -- e.g., for an NFS directory with many files. Some file systems have special logging features that can introduce additional delays to the building of the search list -- e.g., NFS logging, or logging on a Solaris UFS file system. The bottom line is that slow search list construction may not be so much an lsof problem as a file system problem. (Hint: if you're using Solaris UFS logging, consider specifying the "logging,noatime" option pair to reduce the number of atime writes to the UFS logging queue and disk.) A somewhat risky way to speed up lsof's building of the search list is to use lsof's ``-O'' option. It forces lsof to do all system calls needed to build the search list directly, rather than in a child process. While direct system calls are much faster, they can block in the kernel -- e.g., when an NFS server stops responding -- stopping lsof until the kernel operation unblocks. As an example of the load +D can impose, consider that an `lsof +D /` on a lightly loaded NeXT '040 cube with a 1GB root file system disk took 4+ minutes of real time. It also generated several hundred error messages about files and directories the lsof process didn't have permission to access with stat(2). The bottom line is that +D and +d should be used cautiously. +D is more costly than +d for deeply nested directory trees, because of the full directory descent it causes. So use +d where possible. And you might need to consider the performance of the file system that holds the directory you name with +d or +D. In view of these warnings, when is it appropriate to use +D or +d? Probably the most appropriate time is when you would specify the directory's contents to lsof with a shell globbing construct -- e.g., `lsof *`. If that's what you need to do, `lsof +d .` is probably more efficient than having the shell produce a directory list, form it into an argument vector, and pass the vector to lsof for it to unravel. See the answer to the question "Why do the +D and +d options produce warning messages?" for an explanation of some process authority limitations of +D and +d. 3.21.6 Why do the +D and +d options produce warning messages? +D and +d option processing is limited by the authority of the lsof process -- i.e., lsof can only examine (with lstat(2) and stat(2)) files the owner of the process can access. If the ownership, group membership, or permissions of the specified directory, file within it, or directory within it prevents the owner of the lsof process from using lstat(2) or stat(2) on it, lsof will issue a warning message, naming the path and giving the system's (lstat(2's or stat(2)'s) reason (errno explanation text) for refusing access. As an example, assume user abc has a subdirectory in /tmp, owned by abc and readable, writable and searchable by only its owner. If user def asks lsof to search for all /tmp references with +D or +d, lsof will be unable to lstat(2) or stat(2) anything in abc's private subdirectory, and will issue an appropriate warning. Lsof warnings can usually be suppressed with the -w option. However, using -w with +D or +d means that there will be no indication why lsof couldn't find an open reference to a restricted directory or something contained in it. Hint: if you need to use +D or +d and avoid authority warnings, and if you have super-user power, su and use lsof with +D or +d as root. 3.22 Why can't my C compiler find the rpcent structure definition? When you try to compile lsof your compiler may complain that the rpcent structure is undefined. The complaints may look like this: >print.c: In function `fill_portmap': >print.c:213: dereferencing pointer to incomplete type >... The most likely cause is that someone has allowed a BIND installation to update /usr/include/netdb.h (or perhaps /usr/include/rpc/netdb.h), removing the rpcent structure definition that lsof expects to find there. Only Solaris has an automatic work-around. (See dlsof.h in dialects/sun.). The Solaris work-around succeeds because there is another header file, <rpc/rpcent.h>, with the rpcent structure definition, and there is a Solaris C pre-processor test that can tell when the BIND <netdb.h> is in place and hence <rpc/rpcent.h> must be included. Doubtlessly there are similar work-arounds possible in other UNIX dialects whose header files have been "touched" by BIND, but in general I recommend restoration of the vendor's <netdb.h> and any other header files BIND might have replaced. (I think BIND replaces <resolv.h>, <sys/bitypes.h>, <sys/cdefs.h> -- and maybe others.) 3.23 Why doesn't lsof report fully on file "foo" on UNIX dialect "bar?" Lsof sometimes won't report much information on a given file, or may even report an error message in its NAME column. That's usually because the file is of a special type -- e.g., in a file system specific to the UNIX dialect -- and I haven't used a system where the file appeared during my testing. If you encounter such a situation, send me e-mail at <abe@purdue.edu> and we may be able to devise an addition to lsof that will report on the file in question. Please follow the reporting guidelines in the "How do I report an lsof bug?" section of this FAQ. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 3.24 Why do I get a complaint when I execute lsof that some library file can't be found? On systems where the LIBPATH (or the equivalent) environment variable is used to record the library search path in executable files when they are built, an incorrect value may make it impossible for the system to find the shared libraries needed to load lsof for execution. This may be particularly true on systems like AIX >= 4.1.4, where the lsof Makefile takes the precautionary step of using the -bnolibpath loader flag to insure that the path to the private static lsof library is not recorded in the lsof binary. Should LIBPATH be invalid when lsof is built, it will be recorded in the lsof binary as the default library path search order and lead to an inability to find libraries when lsof is executed. So, if you get missing library complaints when you try to execute lsof, check LIBPATH, or whatever environment variable is used on your system to define library search order in executable files. Use the tools at your disposal to look at the library paths recorded in the lsof binary -- e.g., chatr on HP-UX, dump on AIX, ldd on Solaris. Make sure, too, that when the correct library search path has been recorded in the executable file, the required library files exist at one or more of the search paths. 3.25 Why does lsof complain it can't open files? When lsof begins execution, unless it has been asked to report only help or version information, typically it will attempt to access kernel memory and symbol files -- e.g., /unix, /dev/kmem. Even though lsof needs only permission to open these files for reading, read access to them might be restricted by ownerships and permission modes. So the first step to diagnosing lsof problems with opening files is to use ls(1) to examine the ownerships and permission modes of the files that lsof wants to open. You may find that lsof needs to be installed with some type of special ownership or permission modes to enable it to open the necessary files for reading. See the "Installing Lsof" section of 00README for more information. 3.26 Why does lsof warn "compiled for x ... y; this is z."? Unless warnings are suppressed (with -w) or the kernel identity check symbol (HASKERNIDCK) definition has been deleted, all but one lsof dialect version (exception: /proc-based Linux lsof) compare the identity of the running kernel to that of the one for which lsof was constructed. If the identities don't match, lsof issues a warning like this: lsof: WARNING: compiled for Solaris release 5.7; this is 5.6. Two kernel identity differences can generate this warning -- the version number and the release number. Build and running identity differences are usually significant, because they usually indicate kernels whose structures are different -- kernel structures commonly change at dialect version releases. Since lsof reads data from the kernel in the form of structures, it is sensitive to changes in them. The general rule is that an lsof compiled for one UNIX dialect version will not work correctly when run on a different version. There are three work-arounds: 1) use -w to suppress the warning -- and risk missing other warnings; 2) permanently disable the identity check by deleting the definition of HASKERNIDCK in the dialect's machine.h header file -- with the same risk; or 3) rebuild lsof on the system where it is to be run. (Deleting HASKERNIDCK can be done with the Customize script or by editing machine.h.) Generally checking kernel identity is a quick operation for lsof. However, it is potentially slow under AIX, where lsof must run /usr/bin/oslevel. To speed up lsof, use -w to suppress the /usr/bin/oslevel test. See "Why does AIX lsof start so slowly?" for more information. 3.27 How can I disable the kernel identity check? The kernel identity check is controlled by the HASKERNIDCK definition. When it is defined, most dialects (exclusion: /proc-based Linux lsof) will compare the build-time kernel identity with the run-time one. To disable the kernel identity check, disable the HASKERNIDCK definition in the dialect's machine.h header file. The Customize script can be used to do that in its section about the kernel identity check. Caution: while disabling the kernel identity check may result in smaller lsof startup overhead, it comes with the risk of executing an lsof that may produce warning messages, error messages, incorrect output, or no output at all. 3.28 Why don't ps(1) and lsof agree on the owner of a process? Generally the user ID lsof reports in its USER column is the process effective user ID, as found in the process structure. Sometimes that may not agree with what ps(1) reports for the same process. There are sundry reasons for the difference. Sometimes ps(1) uses a different source for process information, e.g., the /proc file system or the psinfo structure. Sometimes the kernel is lax or confused (e.g., Solaris 2.5.1) about what ID to report as the effective user ID. Sometimes the system carries only one user ID in its process structure (some BSD derivatives), leaving lsof no choice. The differences between lsof and ps(1) user identifications should be small and normally it will be apparent that the confusion is over a process whose application has changed to an effective user ID different from the real one. 3.29 Why doesn't lsof find an open socket file whose connection state is past CLOSE_WAIT? TCP/IP connections in states past CLOSE_WAIT -- e.g., FIN_WAIT_1, CLOSING, LAST_ACK, FIN_WAIT_2, and TIME_WAIT -- don't always have open files associated with them. When they don't, lsof can't identify them. When the connection state advances from CLOSE_WAIT, sometimes the open file associated with the connection is deleted. 3.30 Why don't machine.h definitions work when the surrounding comments are removed? The machine.h header files in dialect subdirectories have some commented-out definitions like: /* #define HASSYSDC "/your/choice/of/path */ You can't simply remove the comments and expect the definition to work. That's intended to make you think about what value you are assigning to the symbol. The assigned value might have a system-specific convention. HASSYSDC, for example, might be /var/db/lsof.dc for FreeBSD, but it might be /var/adm/lsof.dc for Solaris. Symbols defined in the lsof documentation are described in 00PORTING, other machine.h comments, and other lsof documentation files. HASSYSDC, for example, is discussed in 00DCACHE. When comments and documentation don't suffice, consult the source code for hints on how the symbol is used. 3.31 What do "can't read inpcb at 0x...", "no protocol control block", "no PCB, CANTSENDMORE, CANTRCVMORE", etc. mean? Sometimes lsof will report "can't read inpcb at 0x00000000", "no protocol control block", "no PCB, CANTSENDMORE, CANTRCVMORE" or a similar message in the NAME column for open TCP socket files. These messages mean the file's socket structure lacks a pointer to the INternet Protocol Control Block (inpcb) where lsof expects to find connection addresses -- local and foreign ports, local and foreign IP addresses. The socket file has probably been submitted to the shutdown(2) function for processing. In some implementations lsof issues the "no PCB, CANTSENDMORE, CANTRCVMORE" message, which tries to explain the absence of a protocol control block by showing the socket state settings that have been made by the shutdown(2) function. If a non-zero address follows the "0x" in the "can't read inpcb" message, it means lsof couldn't read inpcb contents from the indicated address in kernel memory. 3.32 What do the "unknown file system type" warnings mean? Lsof may report a message similar to" unknown file system type, v_op: 0x10472f10 in the NAME column for some files. This means that lsof has encountered a vnode for the file whose operation switch address (from v_op) references a file system type for which there is no support in lsof. After lsof identifies the file system type, it uses pre-compiled code to locate the file system specific node for the file where lsof finds information like file size, device number, node number, etc. To get some idea of what the file system type might be, use nm on your kernel symbol file to locate the symbol name that corresponds to the v_op address -- e.g., on Solaris do: $ nm -x /dev/ksyms | grep 0x10472f10 0x10472f10 ... |file_system_name_vnodeops Where "file_system_name" is the clue to the unsupported file system. Lsof doesn't use the v_op address to identify file system types on all dialects. Sometimes it uses an index number it finds in the vnode. It will translate that symbol to a short name in the warning message -- e.g., "nfs3" -- if possible. 3.33 Installation 3.33.1 How do I install lsof? There is no "standard" way to install lsof. Too much depends on local conditions for me to be able to provide working install rules in the lsof make files. (The skeleton install rules you will find just give "hints.") See the "Installing Lsof" section of 00README for a fuller explanation. To install lsof you will need to consider these questions: * Who should be able to use lsof? (See HASSECURITY and HASNOSOCKSECURITY in the "Security" section of 00README.) * Where should lsof be installed? This is a decision mostly dictated by local conditions. Somewhere in /usr/local -- etc/ or sbin/ -- is a common choice. * What permissions should I give the lsof executable? The answer to this varies by dialect. The make files have install rules that give hints. The "Installing Lsof" section of 00README gives information, too. * What if I want to install lsof in a shared file system for machines that require different lsof configurations? See the next question and answer, "How do I install a common lsof when I have machines that need differently constructed lsof binaries?" 3.33.2 How do I install a common lsof when I have machines that need differently constructed lsof binaries? A dilemma that faces some system administrators when they install lsof in a shared file system -- e.g., NFS -- is that they must have different lsof executables for different systems. The answer is to build an lsof wrapper script that is executed in place of lsof. The script can use system commands to determine which lsof binary should be executed. Consider this example. You have HP-UX machines with 32 and 64 bit kernels that share the /usr/local/sbin directory where you want to install lsof. Consequently, on each system you must use a different lsof executable, built for the system's bit size. (That's because lsof reads kernel structures, sized by the kernel's bit size.) One answer is to install three things in /usr/local/sbin: 1) a 32 bit lsof as lsof32; 2) a 64 bit lsof as lsof64; and 3) an lsof script. The script might look like this one, based on work by Amir J. Katz: #!/bin/sh x=`/usr/bin/getconf KERNEL_BITS` # returns 32 or 64 if /usr/bin/test "X$x" = "X32" then lsof32 $* else if /usr/bin/test "X$x" = "X64" then lsof64 $* else echo "Can't determine which lsof executable to use;" echo "getconf KERNEL_BITS says: $x" exit 1 fi fi Solaris users should consult "How do I install lsof for Solaris 7, 8 or 9?" for information on a similar trick using the Solaris isaexec command. Users of other dialects might be able to use a command like uname(1) that can identify a distinguishing feature of the system to be incorporated in pre-installed lsof executable names. For example, use `uname -r` and install binaries with suffixes that match `uname -r` output. 3.34 Why do lsof 4.53 and above reject device cache files built by earlier lsof revisions? When lsof revisions 4.53 run and encounter a device cache file built by an earlier revision, it will reject the file and build a new one. The rejection will be advertised with these messages: lsof: WARNING: no /dev device in <name>: 2 sections ... lsof: WARNING: created device cache file: <name> This happens because the header line of the device cache file was changed at revision 4.53 to contain the number of the device on which the device directory resides. The old device cache file header line -- the "2 sections" line in the above warning message, node reads "2 sections, dev=600". This is not a serious problem, since lsof automatically rebuilds the device cache file with the correct header line. 3.35 What do "like block special" and "like character special" mean in the NAME column? When lsof comes across an open block or character file whose device, raw device and inode place it somewhere other than /dev (or /devices), lsof doesn't report the /dev (or /devices) name in the NAME column. Instead lsof reports the file system name and device or path name in the NAME column and parenthetically adds "like block special <path>" or "like character special <path>". The value for <path> will point to a block or character device in /dev (or /devices) whose raw device number matches that of the open file being reported, but whose device number or node number (or both) don't match. Such an open file is connected to a device node that has been created in a directory other than /dev (or /devices.) See mknod(8) for information on how such nodes are created. (Generally one needs root power to create device nodes with mknod.) 3.36 Why does an lsof make fail because of undefined symbols? When lsof is compiled via the `make` step and the final load step fails because of missing symbols, the problem may not be lsof. The problem may be that ld, called by the compiler as part of the `make` step, can't find some library that lsof needs. First check the last compiler line of the make operation -- e.g., the last line with cc or gcc in it before the undefined symbol report -- for loader arguments, i.e., ones beginning with "-l". Except for "-llsof" the rest name system libraries. ("-L./lib" precedes "-llsof" to tell the loader its location.) Check that all the named system libraries exist. Look in /lib and /usr/lib as a start, but that may not be the only place system libraries live. Consult your dialect's documentation, e.g., the compiler and loader man pages, for other possible locations. If some system library doesn't exist, that may mean it was never installed or was removed. You'll have to re-install the missing library. You may find that all the system libraries lsof uses exist. Your next step might be to use nm and grep to see if any of them contain the undefined symbols. $ nm library | grep symbol If the undefined symbol exists in some library named by the lsof make step, then you might have a problem with some environment variable that controls the load step. The most common is LD_LIBRARY_PATH. It may have a setting that causes ld to ignore a directory containing a library lsof names. If this is the case, try unsetting LD_LIBRARY_PATH in the environment of the ld process -- e.g., do: $ unset LD_LIBRARY_PATH or % unsetenv LD_LIBRARY_PATH Consult your ld man page for other environment variables that might affect library searching -- e.g., LIBPATH, LPATH, SHLIB_PATH, etc. If the undefined function doesn't exist in any libraries lsof names, check other libraries. See if the function has a man page that names its library. If the latter is true, please let me know, because that is an lsof problem I need to fix. If none of these solutions work for you, send me some documentation via e-mail at <abe@purdue.edu>. Include `uname -a` output, the output of the lsof `Configure ...` and `make` steps, and the contents of the environment in force when the `make` step was executed -- e.g., `env` or `printenv` output. If you've located the libraries lsof names, send me that information, too. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 3.37 Command Regular Expressions (REs) 3.37.1 What are basic and extended regular expressions? Lsof's ``-c'' option allows the specification of regular expressions (REs), enclosed in two slash ('/') characters and followed by these modifiers: b the RE is a basic RE. i ignore case. x the RE is an extended RE (the default). Note: the characters of the regular expression may need to be quoted to prevent their expansion by the shell. Example: this RE is an extended RE that matches exactly four characters, whose third may be an upper ('O') or lower case ('o') oh: -c /^..o.$/i For simplicity's sake, an RE that is acceptable to egrep(1) is usually called an extended RE. REs suitable for the old line editor, ed(1), are often called basic REs (and sometimes also called obsolete). These are some ways basic REs usually differ from extended REs. (There are other differences.) * `|', `+', `?', '{', and '}' are ordinary characters. * `^' is an ordinary character except at the beginning of the RE. * `$' is an ordinary character except at the end of the RE. * `*' is an ordinary character if it appears at the beginning of the RE. For more information on REs and the distinction between basic and extended REs, consult your dialect's man pages for ed(1), egrep(1), sed(1), and possibly regex(5) or regex(7). 3.37.2 Why can't I put a slash in a command regular expression? Since a UNIX command name is the last part of a path to the command's executable, the lsof command regular expression (RE) syntax uses slash ('/') to mark the beginning and end of an RE. Slash may not appear in the RE and the `\' back-slash escape is ineffective for "hiding" it. More likely than not, if you try to put a slash in an lsof command RE, you'll get this response: $ lsof -s/.\// ... lsof: invalid regexp modifier: / Lsof is complaining the the first character it found after the second slash isn't an lsof command RE modifier -- 'b', 'i', or 'x'. 3.37.3 Why does lsof say my command regular expression wasn't found? When you use both forms of lsof's -c option -- ``-c <command>'' and ``-c /RE/[m]'' -- and ask that lsof do a verbose search (``-V''), you may be surprised that lsof will say that the regular expression wasn't found. This can happen if the ``-c <command>'' form matches first, because then the ``-c/RE/[m]'' test will never have been applied. For example: $ ./lsof -clsof -c/^..o.$/ -V -adcwd COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME lsof 7850 abe cwd VDIR 6,0 2048 96442 / (/dev/sd0a) lsof: no command found for regex: ^..o.$ The ``-clsof'' option matched first, so the ``-c/^..o.$/ option wasn't tested. 3.38 Why doesn't lsof report on shared memory segments? Lsof reports on shared memory segments only if they're associated with an open file. That's consistent with lsof's mission -- to LiSt Open Files. Shared memory segments with no file associations aren't open files. That's not to say that a report on shared memory segments and their associated processes wouldn't be useful. But it calls for a new tool, not more baggage for lsof. 3.39 Why does lsof report two instances of itself? When you ask lsof to report all open files and it has permission to do so, you may see two lsof processes in the output. The processes are connected via pipes -- e.g., here's an HP-UX 11 example. COMMAND PID USER FD TYPE DEVICE ... ... lsof 29450 abe 7w PIPE 0x48732408 ... lsof 29450 abe 8r PIPE 0x48970808 ... ... lsof 29451 abe 6r PIPE 0x48732408 ... lsof 29451 abe 9w PIPE 0x48970808 ... The first process will usually be the lsof you initiated; the second, an lsof child process that is used to isolate its parent process from kernel functions that can block -- e.g., readlink() or stat(). Information to and from the kernel functions is exchanged via the two pipes. When the parent process detects that the child process has become blocked, it attempts to kill the child. Depending on the UNIX dialect that may succeed or fail, but the parent won't be blocked in any event. See the "BLOCKS AND TIMEOUTS" and "AVOIDING KERNEL BLOCKS" sections of the lsof man page for more information on why the child process is used and how you can specify lsof options to avoid it. (Caution: that may be risky.) 3.40 Why does lsof report '\n' in device cache file error messages? Lsof revisions prior to 4.58 may report '\n' in error messages it delivers about problems in the device cache file -- e.g., lsof: WARNING: no ...: 4 sections\n That's deliberately done to show the exact contents of the device cache file line about which lsof is complaining, including its terminating NL (New Line) '\n' character. In the above example the line in the device cache file causing the lsof complaint contains "4 sections" and ends with a '\n'. At revision 4.58 and above, device cache error messages like the one in the above example have been changed to read: lsof: WARNING: no ...: line "4 sections" The terminal '\n' is no longer reported, the line contents are enclosed in double quote marks ('"'), and the word "line" has been added as a prefix to denote that what follows is a line from the device cache file. 3.41 Kernel Symbol and Address Problems 3.41.1 What does "lsof: WARNING: name cache hash size length error: 0" mean? When run on some systems, lsof may issue this warning: lsof: WARNING: name cache hash size length error: 0 That is an example from a FreeBSD system where lsof reads the kernel's _nchash variable and finds its value is zero. Similar warnings include: WARNING: kernel name cache size: WARNING: can't read kernel's name cache: WARNING: no name cache address WARNING: name cache hash size length error: WARNING: unusable name cache size: These warnings are issued when lsof is attempting to read the kernel's name cache information. They are usually the result of a mis-match between the addresses for kernel symbols lsof gets via nlist(2) and the addresses in use by the kernel. Lsof usually gets kernel symbol addresses from what it believes to be the kernel boot file. In FreeBSD, for example, that's the path returned by getbootfile(3), usually /kernel. The boot file can have other names in other UNIX dialects -- /unix, /vmunix, /bsd, /netbsd, /mach, /stand/vmunix, etc. Lsof will get incorrect (mismatched) addresses from the boot file if it has been replaced by a newer one which hasn't yet been booted -- e.g., if this is done in FreeBSD: # mv /kernel /kernel.OLD # mv /kernel.NEW /kernel Until the FreeBSD system is rebooted, the booted kernel is /kernel.OLD, but getbootfile() says it is /kernel. If symbol addresses important to lsof in /kernel.OLD and /kernel don't match, the lsof WARNING messages result. 3.41.2 Why does lsof produce "garbage" output? Kernel name cache warnings may not be the only sign that lsof is using incorrect symbol addresses to read kernel values. If there's no reasonable test lsof can make on what it reads from the kernel, it may issue other warnings or even report nonsensical results. The warnings may appear on STDERR, such as: lsof: can't read proc table info Or the warnings may appear in the NAME column as messages saying lsof can't read or interpret some kernel structure -- e.g., ... NAME ... can't read file struct from 0x12345 One possible work-around is to point lsof's kernel symbol address gathering at the proper boot file. That can be done with lsof's -k option -- e.g., $ lsof -k /kernel.OLD The best work-around is to make sure the standard boot file is properly sited -- e.g., if you've moved a new /kernel in place, boot it. 3.42 Why does lsof report open files when run as super user that it doesn't report when run with lesser privileges? The most likely cause is that the HASSECURITY option was selected when the lsof executable was built. If HASSECURITY is defined when lsof is built, and lsof is run with the privileges of a non-ROOT user, it will only list open files belonging to the user. The same lsof executable, when run with root user privileges, will list all open files. However, if HASSECURITY and HASNOSOCKSECURITY are both defined when lsof is built, lsof will list open files belonging to the user and will also list anyone else's open socket files, provided their listing is selected with the "-i" option. So first ask yourself if the process whose open files lsof won't list belong to a user other than the one under which you're running lsof, and are not open socket files. If either is true, use lsof's help (-h or -?) option and look for a line near the bottom of the help panel that says: "... can list all files..." If the leading "..." says "Only root" then HASSECURITY was defined when lsof was built. If the trailing "..." says ", but anyone can list socket files" then HASNOSOCKSECURITY was also defined. Should you want an lsof not built with HASSECURITY defined, rerun the lsof Configure script. If you let Configure do customization, make sure you answer 'n' when it asks if you want to enable HASSECURITY and HASNOSOCKSECURITY. If you don't need to do customization, you can rebuild lsof with the "-n" option to Configure. Here's an example of such a rebuild sequence: $ Configure -clean $ Configure -n <dialect-abbreviation> $ make More information on the HASSECURITY and HASNOSOCKSECURITY options may be found in the "Security" section of the 00README file of the lsof distribution. 3.43 Test Suite Problems 3.43.1 Errors all tests can report: 3.43.1.1 Why do tests complain "ERROR!!! can't execute ../lsof"? All tests in the test suite expect an executable lsof file to exist in the tests parent directory, ../lsof. If there's none there, the tests/Makefile has a rule to make it, but there are probably circumstances where that rule may fail. The work-around is to re-Configure and re-make lsof, then run the test suite. 3.43.1.2 Why do tests complain "ERROR!!! can't find ..." a file? Many tests create (or use from a supplied environment variable path) a test file and use lsof to find it. When lsof can't file the file, the tests report the error with messages of the form: ERROR!!! can't find ... : <some file path> or ERROR!!! lsof couldn't find ... These type of error messages mean that the lsof field output delivered to the test didn't contain a file that the test could identify as the one it intended lsof to find. It might also mean that the process information -- command name, PID or parent PID -- didn't match what the test expected. This could imply a bug in the test or a bug in lsof. Try using lsof to find a known file that is open. For example, while in the tests sub-directory, do this: $ sleep 30 < Makefile $ ../lsof Makefile If lsof doesn't report that Makefile is open, then the fault may be with lsof. If lsof reports the file is open, search further in the test code for the failure cause. 3.43.1.3 Why do some tests fail to compile? If a test suite program fails to compile, it may be because I've never had an opportunity to compile the test on the particular UNIX version you are using. See Appendix B in 00TEST for a list of the UNIX dialects where the test suite has been validate. 3.43.1.4 Why do some tests always fail? There are several tests in the optional group that have conflicting or special requirements: LTbigf needs a dialect and file system that support large files. LTlock won't work if the tests/ sub-directory is on an NFS file system. LTnfs won't work if the tests/ sub-directory is not on an NFS file system. So for two tests in particular, LTlock and LTnfs, one will generally fail. Some failing tests can be run successfully by supplying to them a path to the appropriate type of file system with the -p option. 3.43.1.5 Why does the test suite say it hasn't been validated on my dialect? When you use the default rule of the test suite's Makefile, it may issue this complaint: $ cd tests $ make !!!WARNING!!! This dialect or its particular version may not have been validated with the lsof test suite. Consequently some tests may fail or may not even compile. !!!WARNING!!! You are then given the opportunity to answer 'y' to have the test suite operation continue. This message means that the tests/TestDB file in the tests sub-directory doesn't show that the test suite has been run with the combination of compiler flags found in tests/config.cflags. The tests might nor run; they may encounter compiler failures. See 00TEST for more information on the UNIX dialects where the test suite has been validated and on the workings of TestDB and its supporting scripts. When the tests/Makefile "auto" rule is used, the message is more terse and the condition is fatal. This suite has not been validated on: <dialect_description> No opportunity to continue is offered. The tests/Makefile "silent" rule will skip checking for the validation footprint. 3.43.1.6 Why do the tests complain they can't stat() or open() /dev/mem or /dev/kmem? When the tests detect that lsof for the dialect reads its information from kernel memory (i.e., the LT_KMEM definition is present in tests/config.cflags), and when the lsof executable path is ../lsof, the tests make sure they can stat() and open() for read access the relevant kernel memory devices, /dev/kmem and possibly /dev/mem. If those stat() or open() operations fail, the tests issue an error message and quit. The message explains why the system rejected the operation in terms of system "errno" symbols and messages. More often than not the explanation will be that the process lacks permission to access the indicated device node. One work-around is to give the lsof executable being tested the necessary permission -- e.g., via chgrp, chmod, etc. -- and set its path in the LT_LSOF_PATH environment variable. (See 00TEST.) Another work-around is to make sure the process that runs the tests has the necessary permissions -- e.g., run it as root, or enable the process login to access the resources. For example, I can run the tests on my personal work-station because /dev/kmem and /dev/mem are readable by the "kmem" group and my login is in that group. 3.43.2 LTbigf test issues 3.43.2.1 Why does the LTbigf test say that the dialect doesn't support large files? Large file support is defined dialect by dialect in the lsof source files and Configure script. If large file support isn't defined there, it isn't defined in the LTbigf test. If you think that's wrong for a particular dialect, contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 3.43.2.2 Why does LTbigf complain about operations on its config.LTbigf* file? The LTbigf must be able to write a large file test (size > 32 bits) and seek within it and the process file ulimit size must permit the operation. If the default location for the test file, tests/, isn't on a file system enabled for large file operations or if the process ulimit file block size is too small, lsof will get file operation errors, particularly when seeking There may be a work-around. Specify the path to a file LTbigf can write in a file system enabled for large file operations a the -poption. Make sure that the ulimit file block size permits writing a large file. For example, presuming /scratch23 is large-file-enabled, and presuming you have permission to raise the ulimit file block size, this shell commands will allow the LTbigf test to run on AIX: $ ./LTbigf -p /scratch23/abe/bigfile (Note: syntax for the ulimit command varies by dialect and by shell. Discovering the proper variant is left to the reader.) More information on this subject can be found in the LTbigf description in the 00TEST file. If course, the LTbigf.c source file in tests/ is the ultimate source of information, 3.43.2.3 Why does LTbigf warn that lsof doesn't return file offsets? On some dialects (e.g., Linux) lsof can't report file offsets, because the data access method underlying lsof doesn't provide them. If LTbigf knows that lsof can't report file offsets for the dialect, it issues this warning: LTbigf ... WARNING!!! lsof can't return file offsets for this dialect, so offset tests have been disabled. LTbigf then performs the size test and skips the offset tests. For more information see 00TEST and the "Why doesn't /proc-based lsof report file offsets (positions)?" Q&A of this file. 3.43.3 Why does the LTbasic test complain "ERROR!!! lsof this ..." and "ERROR!!! lsof that ..."? The LTbasic test program uses lsof to examine a running lsof process. It looks for the lsof current working directory, executable (if possible), and kernel memory file (if applicable). Failures to find those things result in the LTbasic error messages. More information on how LTbasic produces the error messages may be found in the LTbasic.c source file. On HP-UX 11.11 and higher, for example, if the test's current working directory is on a loopback (LOFS) file system, LTbasic won't be able to find the current working directory of the lsof process because of a bug in the HP-UX kernel. The solution for that HP-UX problem is to install an HP-UX patch. See the answer to the "Why doesn't PSTAT-based lsof report a CWD that is on a loopback (LOFS) file system?" question for more information on the patch. 3.43.4 NFS test issues 3.43.4.1 Why does the LTnfs test complain "couldn't find NFS file ..."? The LTnfs test must work with an NFS test file. After it opens the file it asks lsof to find it on an NFS file system. If the file isn't on an NFS file system, lsof won't find it, and the NFS test script complains and fails. The work-around is to use -p option to supply a path to a regular NFS file (not a directory) that is on an NFS file system that LTnfs can read. Presuming /share/bin/file is such a file and can be opened for reading by the LTnfs test, this sample shell command could be used to run the LTnfs test successfully: $ ./LTnfs -p /share/bin/file (If the NFS file system is enabled for large files, the NFS test will produce the error message described in the following Q&A.) 3.43.5 LTnlink test issues 3.43.5.1 Why does the LTnlink test complain that its test file is on an NFS file system? The LTnlink test may complain: LTnlink ... WARNING!!! test file <path> is NFS mounted. and then issue an explanation and a hint about using the -p option. The LTnlist test does this because of the way NFS file links are managed when an NFS file is unlinked and the unlinking process still has the file open. Unlike with files on a local file system, when an NFS file that is still open is unlinked, its link count is not reduced. The file name is changed to a name of the form .nfsxxxx and the link count is left unchanged until the process holding the file open closes it. That's done by NFS so it can keep proper track of the file on NFS clients and servers. Since the link count isn't reduced when the LTnlink test program closes the NFS test file it still has open, lsof won't find it for LTnlink with a link count of zero. Consequently, LTnlink disables that test section and issues its warning. The warning suggests that the unlink test section can be run by giving LTnlink a path to a test file with the -p option. That path must name a file LTnlink can write and unlink. Presuming /scratch23/abe/nlinkfile is on a local file system and the LTnlink test can write to it and unlink it, this sample shell command can be used to run the complete LTnlink test successfully: $ LTnlink -p /scratch23/abe/nlinkfile 3.43.5.2 Why does LTnlink delay and report "waiting for link count update: ..."? On some UNIX dialects and file system combinations the updating of link count after a file has been unlinked can be delayed. Consequently, lsof won't be able to report the updated link count to LTnlink for a while. When lsof doesn't report the proper link count to LTnlink, it sleeps and repeats the lsof call, using the "waiting for link count update: ..." message as a signal that it is waiting for the expected lsof response. The wait cycle duration is limited to approximately one minute. 3.43.6 LTdnlc test issues 3.43.6.1 Why won't the LTdnlc test run? Lsof is unable to access the DNLC cache on AIX, because the kernel symbols for the DNLC aren't exported. Contact IBM to learn why that decision was made. The LTdnlc test won't work on Apple Darwin because lsof can't obtain reliable DNLC information. The LTdnlc test may fail on other dialects. Failure causes include: a busy system with a DNLC that is changing rapidly; path name components too large for the DNLC; a file system -- e.g., NFS, /tmp, loopback -- which doesn't fully participate in the DNLC; or DNLC limitations (Many DNLC implementations will only store path name components if they are 31 characters or less.) If you suspect the file system doesn't fully participate in kernel DNLC processing, as a work-around rebuild and test lsof on one that does. 3.43.6.2 What does the LTdnlc test mean by "... <path> found: 100.00%"? Even when it succeeds the LTdnlc test will report: LTdnlc ... /export/home/abe/src/lsof4/tests found: 100.00% This message means that the LTdnlc test asked lsof to find the file at the indicated path five times and lsof found the full path name in the indicated percentage of calls. The LTdnlc test considers it a failure if the percentage falls below 50.0% 3.43.6.3 Why does the DNLC test fail? The DNLC test may fail when some component of the lsof tests/ sub-directory can't be cached by the kernel DNLC. Some kernels have a limit on the length of individual components (typically) 32. 3.43.7 Why hasn't the test suite been qualified for 64 bit HP-UX 11 when lsof is compiled with gcc? When I attempted to qualify lsof for HP-UX 11, compiled with gcc 3.0, the LTsock test failed. I traced the failure to a gcc compilation error. Because LTsock is an important test, I didn't feel that the test suite was qualified if it failed. LTsock compiles and runs correctly on 64 bit HP-UX 11 when compiled with HP's ANSI-C. 3.43.8 LTszoff test issues 3.43.8.1 Why does LTszoff warn that lsof doesn't return file offsets? On some dialects (e.g., Linux) lsof can't report file offsets, because the data access method underlying lsof doesn't provide them. If LTszoff knows that lsof can't report file offsets for the dialect, it issues this warning: LTszoff ... WARNING!!! lsof can't return file offsets for this dialect, so offset tests have been disabled. LTszoff then performs the size test and skips the offset tests. For more information see 00TEST and the "Why doesn't /proc-based lsof report file offsets (positions)?" Q&A of this file. 3.43.9 LTlock test issues 3.44 File descriptor list (the ``-d'' option) problems 3.44.1 Why does lsof reject a ``-d'' FD list? Lsof rejects ``-d'' FD lists that contain both exclusions and inclusions with messages like: lsof: exclude in an include list: ^1 lsof: include in an exclude list: 2 That's because ``-d'' FD lists are processed as ORed lists, so it makes no sense for them to contain both exclusions and inclusions. I.e.,, if a ``-d'' FD list were to contain ``^cwd,1'', the ``^cwd'' member is useless, because the ``1'' member dominates by saying "include only FD 1". That effectively excludes ``cwd'' FD. Note that lists may have multiple members of the same type, exclude or include. They are processed as an ORed set. If an FD isn't excluded by any member of an exclude list, it is selected. If an FD is included by any member of an include list, it is selected. 3.44.2 Why are file descriptors other than those in my FD list reported? The FD list that follows ``-d'' excludes or includes file descriptors, but unless the ``-a'' (AND) option is specified, the FD list selections are ORed to the other selections. For example, the following lsof command will cause all file descriptors to be listed for the lsof command, and all but the cwd descriptor for all other commands, probably not what was intended. $ lsof -clsof -d^cwd Hint: use ``-a'' -- e.g., $ lsof -clsof -a -d^cwd 3.45 How can I supply device numbers for inaccessible NFS file systems? When lsof can't get device numbers for inaccessible NFS file systems via stat(2) or lstat(2), it attempts to get them from the mount table's dev=xxx options. Successes are reported with a warning message that indicates the source of the device number and that output might be incomplete as a consequence of the warnings. Some system mount tables -- e.g., Linux /proc/mounts -- don't have a dev=xxx option. In that case, and provided lsof for the dialect supports them, you can use the +m option to create a mount table supplement file and the "+m m" option to use it. First check the lsof -h (help) output to see if the +m and "+m m" options are supported. If they are, use +m to create a mount table supplement file when all mounted file systems are accessible. Use "+m m" later to make the supplement available when some mounted file systems might not be available. Here's an example that creates a mount supplement file in $HOME/mnt-sup and later makes it available to lsof. $ rm -f $HOME/mnt-sup $ lsof +m > $HOME/mnt-sup ... $ lsof +m $HOME/mnt-sup <other lsof options> If lsof has to get the device number from the supplement, it will issue an informative warning message. The warning can be suppressed with lsof's -w option. Caution! Since the mount table supplement file is static, it is its supplier's responsibility to update it as file system mounts change. For more information, consult the lsof man page. The "ALTERNATE DEVICE NUMBERS" section has useful information on how lsof acquires device numbers when stat(2) or lstat(2) fail. 3.46 Why won't lsof find open files on over-mounted file systems? When a file system, /xyz for example, is mounted on the same mount point as another file system, /abc for example, running lsof with an argument of the path of the first file system's mount point -- the over-mounted one, /abc -- probably will not reveal any files open on /abc. That's because lsof looks for open files on a file system by looking for files with the file system's device number. The two file systems usually have different device numbers and lsof determines the device number search key from the supplied name of the second file system. A general work-around exists only for Linux. On that UNIX dialect, when you know the over-mounted file system's mount point path, you can ask lsof to report on all open files and grep that output for the path of the over-mounted file system mount point. 3.47 What can be done when lsof reports no more space? Many lsof methods cache information in memory, using the dialects malloc() library function. When malloc() can't allocate the requested amount of memory, lsof exits with warning messages similar to this AIX message: lsof: no more dev-ch space at pid 2257750: 0x82a8e600 Lsof then exits immediately and produces no more output. A possible work-around is to increase the memory foot print of the shell that runs lsof. That is often done with the ulimit(1) shell command. 3.48 What if the lsof build encounters ar and ld problems? The lsof main and library Makefiles use the library archiver, ar, and the system loader, ld, applications. Improperly located, installed or configured versions of them may cause the lsof build to encounter errors with them. The application producing the error should identify itself in its error messages. The first thing to check the path of the application that is being used. Try `which ar` or `which ld` to see if perhaps the PATH used during the build might be causing the wrong archiver or loader to be used. If the problem is with the use of the wrong archiver, and it's not possible to correct the PATH to it, try using the LSOF_AR environment variable to specify the path to and arguments for the correct archiver. See 00XCONFIG for more information and note that LSOF_AR must specify the path to the archive application and the arguments for it, less the terminating library and module name arguments. If the problem is with the loader, there is no lsof work- around. That's because lsof calls the loader via the C compiler, so the problem must be fixed at the compiler (system) level. 4.0 AIX Problems 4.1 What is the Stale Segment ID bug and why is -X needed? Kevin Ruderman reports that he has been informed by IBM that processes using the AIX 3.2.x, 4.1[.12345]], 4.2[.1], and 4.3.x kernel's readx() function can cause other AIX processes to hang because of what appears to be file system corruption. This failure, known as the Stale Segment ID bug, is caused by an error in the AIX kernel's journaled segment memory handler that causes the kernel's dir_search() function erroneously to believe directory entries contain zeroes. The process using the readx() call need not be doing anything wrong. Usually the system must be under such heavy load that the segment ID being used in the readx() call has been freed and then reallocated to another process since it was obtained from kernel memory. Lsof uses the readx() function to access library entry structures, based on the segment ID it finds in the proc structure of a process. Since IBM probably will never fix the kernel bug, I've added an AIX-specific option to lsof that controls its use of the readx() function. By default lsof readx() use is disabled; specifying the ``-X'' option enables readx() use. If you want to change the default readx() behavior of AIX lsof, change the HASXOPT, HASXOPT_ROOT, and HASXOPT_VALUE definitions in dialects/aix/machine.h. You can also use these definitions to enable or disable readx() -- consult the comments in machine.h. You may want to disable readx() use permanently if you plan to make lsof publicly executable. When HASXOPT_ROOT is defined, lsof will restrict use of the -X option to processes whose real UID is root; if HASXOPT_ROOT isn't defined, any user may specify the -X option. The Customize script offers the option to change HASXOPT_ROOT when HASXOPT is defined and HASXOPT_ROOT is named in any dialect's machine.h header file. I have never seen lsof cause a problem with its use of readx(), but I believe there is some chance it could, given the right circumstances. 4.1.1 Stale Segment ID APAR Here are the details of the Stale Segment ID bug and IBM's response, provided by Kevin Ruderman. AIX V3 APAR=ix49183 user process hangs forever in kernel due to file system corruption STAT=closed prs TID=tx2527 ISEV=2 SEV=2 (A "closed prs" is one closed with a Permanent ReStriction.) RCOMP=575603001 aix v3 for rs/6 RREL=r320 AIX V4 (internal defect, no apar #) prefix p name 175671 abstract KERMP: loop for ever in dir_search() Problem description: 1. Some user application -- e.g., lsof -- gets the segment ID (SID) for the process private segment of a target process from the process table. 2. The target process exits, deleting the process private segment. 3. The SID is reallocated for use as a persistent segment. 4. The user application runs again and tries to read the user area structure from /dev/mem, using the SID it read from the process table. 5. The loads done by the driver for /dev/mem cause faults in the directory; new blocks are allocated; the size changed; and zero pages created. 6. The next application that looks for a file in the affected directory hangs in the kernel's dir_search() function because of the zero pages. This occurs because the kernel's dir_search() function loops through the variable length entries one at a time, moving from one to the next by adding the length of the current entry to its address to get the address of the next entry. This process should end when the current pointer passes the end of the known directory length. However, while the directory length has increased, the entry length data has not, so when dir_search() reaches the zero pages, it loops forever, adding a length of zero to the current pointer, never passing the end of the directory length. The application process is hung; it can't be killed or stopped. IBM closed the problem with a PRS code (Permanent ReStriction) under AIX Version 3 and had targeted a fix for AIX 4.2. They have recently (I became aware of it September 10, 1996) cancelled the defect report altogether and have indicated they are not going to fix the defect. 4.2 Gcc Work-around for AIX 4.1x When gcc is used to compile lsof for AIX 4.1x, it doesn't align one element of the user structure correctly. Xlc sees the U_irss element as a type "long long" and aligns it on an 8 byte boundary. That's because the default mode of xlc is -qlonglong; when -qlonglong is enabled, the _LONG_LONG symbol is also defined. Gcc sees U_irss as a two element array of type long, because _LONG_LONG isn't defined. Hence gcc aligns the U_irss element array on a 4 byte boundary, rather than an 8 byte one, making the gcc incantation of the user structure 4 bytes shorter than xlc's. When the length of gcc's user structure is supplied as argument 4 to the undocumented getuser() function of the AIX kernel, getuser() rejects it as an incorrect size and returns EINVAL. Lsof has a work-around for this problem. It involves a special test in the Configure script when the "aixgcc" Configure abbreviation is used -- e.g., $ Configure -n aixgcc The test is to compile a small program with gcc and check the alignment of U_irss. If it's not aligned on an 8 byte boundary, the Configure script makes a special copy of <sys/user.h> in ./dialects/aix/aix<AIX_version> whose U_irss will align properly, and generates compile time options to use it. While I have tested this work-around only with 4.1.4, it should work with earlier versions of AIX 4.1. It does not work for AIX 4.2; a different work-around is employed there. (See the next section.) If you want to use this technique to compile other AIX 4.1x programs with gcc for using getuser(), check the Configure script. Stuart D. Gathman identified this gcc AIX alignment problem. 4.3 Gcc and AIX 4.2[.1] Alignment problems with gcc and AIX 4.2[.1] inside the user structure are more severe, because there are some new 64 bit types in AIX that gcc doesn't yet (as of 2.7.x) support. The <sys/user.h> U_irss element problem, discussed in 4.3 above, doesn't exist in 4.2[.1]. The AIX lsof machine.h header file has a work-around, provided by Henry Grebler, that bypasses gcc alignment problems. Later versions of gcc (e.g., 2.8.x) will probably bypass the problems as well. 4.4 Why won't lsof's Configure allow the use of gcc for AIX below 4.1? Gcc can't reliably be used to compile lsof for AIX versions below AIX 4.1 because of possible kernel structure element alignment differences between it and xlc. 4.5 What is an AIX SMT file type? When you run AIX X clients with the DISPLAY environment variable set to ``:0.0'' they communicate with the AIX X server via files whose kernel file structure has an undefined type (f_type == 0xf) -- at least there's no definition for it in <sys/file.h>. These are Shared Memory Transport (SMT) sockets, an artifact of AIXWindows, designed for more efficient data transfers between the X server and its clients. Henry Grebler and David J. Wilson alerted me to the existence of these files. Mike Feldman and others helped me identify them as SMT sockets. The curious reader can find more about SMT sockets in /usr/lpp/X11/README.SMT. 4.6 Why does AIX lsof start so slowly? When AIX lsof starts it compares the running kernel's identity to the one for which it was built, using /usr/bin/oslevel. That comparison can sometimes take a long time to complete, depending on the system's maintenance level and how recently it was examined with oslevel. AIX revisions 4.67 and above for AIX 5 and above don't use oslevel to determine the kernel identity. They use uname(2) instead, and it is much faster. You can skip the oslevel test by suppressing warning messages with lsof's -w option. Doing that carries with it the risk of missing other warning messages, however. You can also disable the kernel identity check by disabling the definition of the HASKERNIDCK symbol by editing AIX machine.h header file or by using the Customize script to disable it. See the "Why does lsof warn "compiled for x ... y; this is z.?" section for more information. 4.7 Why does exec complain it can't find libc.a[shr.o]? When you try to execute lsof you may get this complaint: exec(): 0509-036 Cannot load program ./lsof because of the following errors: 0509-022 Cannot load library libc.a[shr.o]. 0509-026 System error: A file or directory in the path name does not exist. This is probably the result of making lsof when the LIBPATH environment variable contained a directory path that doesn't contain libc.a. You can see what LIBPATH contained when lsof was made by using the dump application on lsof. For example, if LIBPATH contained /foo/bar when lsof was made, you will see this (partial) dump output: $ dump -H lsof ... ***Import File Strings*** INDEX PATH BASE ... 0 /foo/bar To correct the problem, revisit the lsof source directory and remake lsof this way: $ unset LIBPATH; make (sh or ksh) or % unsetenv LIBPATH; make (csh or tcsh) 4.8 What does lsof mean when it says, "no PCB, CANTSENDMORE, CANTRCVMORE" in a socket file's NAME column? When an AIX application calls shutdown(2) on an open socket file, but hasn't called close(2) on the file, the file will remain visible to lsof as an open socket file without any extended protocol information. Lsof reports that state in the NAME column by saying that there is "no PCB" (Protocol Control Block) for the protocol (e.g., TCP in the NODE column). If the open socket file has the state variables SO_CANTSENDMORE and SO_CANTRCVMORE set -- i.e., from the shutdown(2) call -- lsof reports them with the CANTSENDMORE and CANTRCVMORE notes in the NAME column. 4.9 When the -X option is used on AIX 4.3.3, why does lsof disable it, saying "WARNING: user struct mismatch; -X option disabled?" The -X option causes lsof to read the loader information of the user structure from virtual memory via the readx() system call. It does that with the user structure definition from <sys/user.h> that was compiled into the lsof executable. On AIX 4.3.3 there are two different user structure definitions in two separate <sys/user.h> header files, distributed at different times by IBM. If lsof was compiled with one and the kernel on which lsof is being run was compiled with the other, lsof normally won't get correct loader information when it calls readx(). In an attempt to compensate for that difference, lsof makes an independent check of the loader information by getting the user structure's open file count via readx() and comparing it to the open file count obtained independently via getprocs(). When the two counts don't match, lsof tries to read the count (and re-read the loader information) with two offsets, based on observed differences between the two user structures. When one of the three attempts produces a correct open file count, lsof uses its corresponding offset on subsequent readings of the loader information. When none of the three attempts produces a correct open file count, lsof issues the WARNING message and disables -X processing. To eliminate this problem, obtain an lsof binary that matches the kernel of the AIX 4.3.3 system where you want to run lsof. Compiling lsof on the target system is the preferred way to get a matching binary. 4.10 Why doesn't the -X option work on my AIX 5L or 5.[123] system? If your AIX 5L or 5.[123] system uses the ia64 architecture, lsof needs setuid-root permission to be able to do the processing that -X requires. Check the output of `uname -a` to determine the architecture type. The work-around is to give lsof setuid-root permission. 4.11 Why doesn't /usr/bin/oslevel report the correct AIX version? The oslevel man page says, "The oslevel command reports the level of the operating system using a subset of all filesets installed on your system." You can see which fileset is below the expected level with oslevel's -l option. For example, if you believe your system is at AIX level 4.3.3, but oslevel reports 4.3.2, use this oslevel command to find the filesets below 4.3.3: $ /usr/bin/oslevel -l 4.3.3.0 If you don't know what level argument to supply to oslevel's -l option, use oslevel's -q option first. 4.11.1 Why doesn't /usr/bin/oslevel report the correct AIX version on AIX 5.1? The subset list for oslevel on AIX 5.1 seems to include at least two filesets, xlsmp.msg.en_US.rte and xlsmp.rte, that do not install from AIX 5.1 media with a 5.1.0.0 level. Hence, oslevel reports 5.0.0.0 instead of the expected 5.1.0.0. If either xlsmp.msg.en_US.rte or xlsmp.rte is installed, lsof's Configure script and run-time tests will identify the AIX version incorrectly. The run-time test will issue a complaint message of this form: lsof: WARNING: compiled for AIX version xxx; this is yyy. You can correct the Configure test by pre-defining the oslevel value, setting the correct value in the LSOF_VSTR environment variable before running the Configure script -- e.g., to pre-define AIX 5.1 when using ksh, do this: $ LSOF_VSTR=5.1.0.0 Configure -n aix You can't affect oslevel output without uninstalling xlsmp.msg.en_US.rte and xlsmp.rte. If you can't do that, you'll have to put up with the run-time complaint. 4.12 Why does lsof for AIX 5.1 or above Power architecture complain about kernel bit size? When you run an lsof binary on an AIX 5.1 or above Power system, it might complain: lsof: FATAL: compiled for a 32 bit kernel. The bit size of this kernel is 64. or exec: 0509-036 Cannot load program ./lsof because of the following errors: 0509-032 Cannot run a 64-bit program on a 32-bit machine. Starting at lsof revision 4.61, lsof binaries for Power architecture systems running AIX 5.1 or above are closely tied to the kernel bit size. Lsof must do that so it can read and understand kernel structures. Lsof's Configure script tunes the lsof configuration so that the binary built in the make(1) step is adjusted to the kernel bit size. An lsof binary knows the bit size for which it was constructed, tests the bit size of the kernel under which it is running, and objects if the two sizes don't match. To see the bit size for which lsof was constructed, run it with its -v option and look for these lines in the output: configuration info: 32 bit kernel or configuration info: 64 bit kernel (Note: these lines will appear only in -v output for AIX 5.1 and above lsof binaries, built for Power architecture.) You can see the kernel bit size test method in the aix stanza of the lsof Configure script and in the get_kernel_access() function of the lsof .../dialects/aix/dproc.c source file. There is more information on pre-defining the kernel bit size when building lsof in Configure, 00PORTING, and 00XCONFIG. The only work-around is to use an lsof binary built to match the running kernel bit size. 4.13 What can't gcc be used to compile lsof on the ia64 architecture for AIX 5 and above? Gcc can't be used to compile lsof on the ia64 architecture for AIX 5 and above because I haven't had access to a system that has a working gcc compiler. The gcc compiler on my one and only ia64 AIX 5.1 test system, provided by IBM, didn't work at all. 4.14 Why does lsof get a segmentation fault when compiled with gcc for a 64 bit Power architecture AIX 5.1 kernel? When lsof is configured with the lsof "aixgcc" Configure abbreviation, the resulting lsof executable may cause a segmentation violation when it is run. I've observed this with gcc version 2.9-aix43-010414-7. As far as I have been able to tell, the segmentation fault is the result of a gcc compilation, loading, or library error. Watching lsof run with gcc's companion debugger, gdb, shows no error in the lsof source code that might explain the fault. The only work-around I know is to use the IBM C compiler in place of gcc -- i.e., use the "aix" lsof Configure abbreviation. 4.15 Why does lsof ignore AFS on my AIX system? The lsof Configure script quits on AIX when AFS is present, the AIX version is greater than 4.3.3.0 or the AFS version is greater than 3.5. That's because I have no test systems available for those AIX and AFS version combinations. When the lsof Configure script detects an AIX and AFS version combination that is unsupported, it will report: !!!FATAL: Lsof does not support AFS on this combination of AIX and AFS versions. To disable AFS, set the value of the AIX_HAS_AFS environment variable to "no". The only work-around is to set the AIX_HAS_AFS environment variable as explained in the error message: $ AIX_HAS_NSF=no; export AIX_HAS_NFS $ ./Configure -n aix 4.16 Why does lsof report "system paging space is low" and exit? When AIX paging space runs low, the AIX kernel sends a SIGDANGER signal to processes, warning them that they should reduce their memory usage. When lsof receives that signal, it issues the following fatal error message and exits: lsof: FATAL: system paging space is low. A possible work-around is to limit the amount of information lsof must cache in its process memory with the "-c", "-g", "-l" and "-p" options. Also see the answer to the "What can be done when lsof reports no more space?" question. 4.17 Why does lsof have a compilation problem on AIX 5.3 above maintenance level 1? On some AIX 5.3 systems with maintenance levels 2 and higher installed, lsof 4.77 and below may not compile properly. The compiler complains the snapshotObject structure definition, needed by <j2/j2_inode.h>, is missing. That problem is fixed in the 4.78 revision. 5.0 Apple Darwin Problems 5.1 What do /dev/kmem-based and libproc-based mean? Lsof for Apple Darwin currently uses /dev/kmem to read kernel data structures from which it gathers and reports open file information. That version of lsof is called /dev/kmem-based lsof. At an upcoming release lsof will use a library called libproc to obtain information about open files. That version of lsof wil be called libproc-based lsof. The /dev/kmem-based lsof sources may be found in the kmem subdirectory of the dialects/darwin branch of the lsof source tree. When the supporting version of Apple Darwin is released, the libproc-based lsof sources will be found in .../dialects/darwin/libproc. 5.2 /dev/kmem-based Apple Darwin Questions 5.2.1 Why does Configure ask for a path to the Darwin XNU kernel header files? When lsof was ported to Apple Darwin by Allan Nathanson at revision 4.53, some kernel header files needed by lsof weren't being exported by the developers. (That's still true at lsof revision 4.76.) At first a shell script that Allan provided would get the missing header files by checking them out from the CVS root. Although the script was updated from time to time, eventually the re-organization of Darwin sources has made it impossible to update the script to do an automatic download of the missing header files. At lsof revision 4.69 and above it is necessary for the Darwin lsof builder to download the Darwin XNU kernel headers before attempting to build lsof. The download my be done via a web browser, starting at this URL: http://www.opensource.apple.com/darwinsource/index.html Once there, select the link to the Mac OS X version that matches the one on the system where lsof is to be built. Follow that link's "[ Source ]" link. Once there, select the tar.gz link of the xnu* entry near the bottom of the page. That entry should have a name that matches the xnu* name shown by `uname -a` -- e.g., if uname reports: $ uname -a ... root:xnu/xnu-517.7.21 ... Then the appropriate xnu* entry is xnu-517.7.21. Clicking its link should lead to an "Apple Open Source" page requesting an Apple ID and password. Enter them if they're available. If an Apple ID and password are not available, get them by following the instructions on the page -- i.e., follow the signin.apple.com link. Once a valid Apple ID and its password have been entered, the download will begin. Select the saving of the downloaded xnu*.tar.gz file in an appropriate place on the Mac OS X system. Once the download completes, install it. Use gunzip to decompress the download and tar to extract the archive -- e.g., $ gunzip -c xnu-517.7.21.tar.gz | tar xf - Remember the absolute path to the extracted archive. That is its installed place. E.g., if the xnu-517.7.21.tar archive was extracted to the lsof builder's home directory, its full installation path will be something like: ~/xnu-517.7.21 Now run the lsof Configure script. When it asks for the path to the installed Darwin XNU kernel header files, supply the path to the gunzip'd and extracted xnu* archive -- e.g., ~/xnu-517.7.21. The path to the Darwin XNU kernel headers may also be supplied to the Configure script in the DARWIN_XNUDIR environment variable, eliminating the need to enter it interactively -- e.g., $ DARWIN_XNUDIR=~/xnu-344.49 ./Configure -n darwin 5.2.1.1 Why does Configure complain that Darwin XNU kernel header files are missing? These are some reasons why the lsof Configure script might claim that Darwin XNU header files are missing: * The wrong path to them was specified. * The files and directories in the path are not readable and searchable -- i.e., check the modes and ownerships. * The downloaded archive doesn't match the Mac OS X version of the system. If in doubt, revisit the Darwin XNU kernel header file download instructions in the answer to the question "Why does Configure ask for a path to the Darwin XNU kernel header files?" If Configure still can't find Darwin XNU kernel header files, contact me via e-mail at <abe@purdue.edu> for help. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 5.2.2 Why doesn't Apple Darwin lsof report text file information? At the first port of lsof to Apple Darwin, revision 4.53, insufficient information was available -- logic and header files -- to permit the installation of VM space scanning for text files. As of lsof 4.70 it is sill not available. Text file support will be added to Apple Darwin lsof after the necessary information becomes available. 5.2.3 Why doesn't Apple Darwin lsof support IPv6? At the first port of lsof to Apple Darwin, revision 4.53, Apple Darwin lacked IPv6 support. IPv6 became available in Apple Darwin version 1.5 and support for it was added to lsof then. 5.2.4 Why does lsof complain about a mismatch between the release for which lsof was compiled and the booted Mac OS X release? When lsof is started on the "Gold Master" Darwin release (aka Mac OS X), it complains: lsof: compiled for 1.0 release; this is 1.3.2. This happens because the lsof binary released with Mac OS X was built on a system whose release number (1.0) doesn't match that of the released system -- usually 1.3.x Lsof makes this check because UNIX dialect OS changes are often accompanied by header file changes that affect lsof. In this specific case, this error can be ignored. If you don't want to do that, get the lsof distribution and build lsof so its built-on and running-on Mac OS X release numbers match. 5.2.5 Why does lsof for Apple Darwin 8 and higher report "stat(...): ..." in the NAME column? Lsof for Apple Darwin 8 may report messages like these in the NAME column: stat(/private/var/run/asl_prune): No such file or directory or stat(/private/var/db/netinfo/local.nidb/Config): Permission denied Those messages indicate that lsof was unable to collect open file information for the paths enclosed in "stat(...)" with the stat(2) function, because the function encountered the reported error. A work-around for the "Permission denied" error is to run lsof with elevated privileges -- e.g., when logged on as the super user. If the stat(2) error message is "No such file or directory", the file probably has been unlinked (removed) and there is no lsof work-around. 5.2.6 What are the limitations of Apple Darwin lsof link count reporting? Lsof for Apple Darwin cannot report link count information reliably. For Apple Darwin below 8 link count information is not always available in the kernel node structures available to lsof. When link count information is available, however, it includes link counts of zero. Thus, using lsof's +L1 option may result in the finding of some files whose link counts are zero. Lsof can report only some link count information for Apple Darwin 8 and above. Link count information is only available for files where lsof can assemble the full file path and has permission to apply stat(2) to it. (See the answer to the "Why does lsof for Apple Darwin 8 and higher report "stat(...): ..." in the NAME column?" question for more information on stat(2) failures.) Apple Darwin 8 and above files that have been unlinked and thus have a link count of zero cannot be found by stat(2) -- i.e., stat(2) returns a "No such file or directory" error. As a result lsof never displays link counts of zero and the use of lsof's +L1 option to find them always fails. 5.3 Libproc-based Apple Darwin Questions 6.0 BSD/OS BSDI Problems 6.0.5 Statement of deprecation As of lsof revision 4.76 support for BSDI BSD/OS has been dropped. The 4.76 distribution of lsof for BSDI BSD/OS may be found on lsof.itap.purdue.edu in pub/tools/unix/lsof/OLD/src. 7.0 DEC OSF/1, Digital UNIX, and Tru64 UNIX Problems 7.1 Why does lsof complain about non-existent /dev/fd entries? When you run lsof for Digital UNIX 3.2, lsof may complain: lsof: can't lstat /dev/fd/xxx: No such file or directory lsof: can't lstat /dev/fd/yyy: No such file or directory (Or it may warn about other missing /dev/fd paths.) When you do an ``ls /dev/fd'' none of the missing paths are listed. This is caused by a bug in the DEC library function getdirentries(). For some reason, when /dev/fd is a file system mount point, getdirentries() returns an incorrect size for it to readdir(). (Lsof calls readdir() in its ddev.c readdev() function.) Because of the incorrect size, readdir() goes past the end of the /dev/fd directory buffer, encounters random paths and returns them to lsof. Lsof then attempts to lstat(2) the random paths, gets error replies from lstat(2), and complains about the paths. Duncan McEwan discovered this error and has reported it to DEC. Duncan also supplied an alternate readdir() function as a work-around. I've incorporated his readdir() in dialects/osf/ddev.c (as the static ReadDir() function) with some slight modifications, and enabled its use when the USELOCALREADDIR symbol is defined. The Configure script defines USELOCALREADDIR for Digital UNIX version and 3.2. If you don't want to use Duncan's local readdir() function, edit the Makefile and remove -DUSELOCALREADDIR from the CFGF string. When DEC releases a corrected getdirentries() function, I'll modify the Configure script to stop defining USELOCALREADDIR. 7.2 Why does the Digital UNIX V3.2 ld complain about Ots* symbols? When you compile lsof on your Digital UNIX V3.2 system, ld may complain: ld: Unresolved: knlist _OtsRemainder32Unsigned _OtsDivide64Unsigned _OtsRemainder64Unsigned _OtsDivide32Unsigned _OtsMove _OtsDivide32 _OtsRemainder32 *** Exit 1 Chris Eleveld reports this happens on Digital UNIX V3.2 systems after the Fortran compiler has been installed. The best work-around seems to be to remove -lmld from the CFGL string in the Makefile produced by Configure -- i.e., change: CFGL= -lmld to CFGL= According to the V3.2 man page for nlist(3), this shouldn't work, but my testing shows that it does. Although I haven't been able to test this second work-around, you might try adding -lots to CFGL, rather than removing -lmld -- i.e., change: CFGL= -lmld to CFGL= -lmld -lots WARNING: my testing also shows that the V2.0 nlist(3) man page means what it says when it calls for -lmld -- lsof loaded without -mld under V2.0 can't locate the proc (process) table address. DON'T REMOVE -lmld FROM THE DIGITAL UNIX V2.0 MAKEFILE. If you run into this problem, please let me know what problem you encountered and how you solved it. 7.3 Why can't lsof locate named pipes (FIFOs) under V3.2? While lsof for V3.2 can report on named pipes (FIFOs), it can't find them by name. That appears to happen because of the way the V3.2 kernel lstat(2) function reports named pipe device numbers. The V3.2 kernel reports the device number as 0xfffffff, while the kernel structures for named pipes that lsof examines contain the device number of the file system on which the named pipe resides. Consequently, lsof can't match the device and inode number pair it receives from applying lstat(2) to the named pipe with any device and inode number pair it finds when scanning kernel structures. I don't have a work-around. You can, of course, ask for full lsof output and use a post-processing filer (e.g., grep) to locate the named pipe of interest. This problem doesn't exist under V2.0. 7.4 Why does lsof use the wrong configuration header files? For example, why can't the lsof compilation find cpus.h? DEC OSF/1, Digital UNIX, and Tru64 UNIX configuration header files describe the hardware and software environment for which your kernel boot file was constructed. For example, /sys/<name>/cpus.h defines the number of CPUs in its NCPUS #define. Lsof searches for the configuration header file subdirectory in /sys (/usr/sys for Digital UNIX version 4.0 and Tru64 UNIX) by converting the first host name component to capital letters -- e.g., TOMIS is derived from tomis.bio.purdue.edu. If that subdirectory exists, lsof uses header files from it. (Configure reports what subdirectory is being used.) If Configure doesn't find a host-name derived subdirectory, it prompts you for the entry of a subdirectory name. If you can't find one, quit Configure and run the kernel generation process to create a proper configuration sub- directory. If you don't identify a proper configuration subdirectory and you try to compile lsof, the compiler will complain about missing header files -- e.g., a missing cpus.h. Once you have located or generated a proper configuration subdirectory, rerun Configure. If you have generated a configuration subdirectory whose name is derived from the host name, Configure will find and use it. If not, you will have to specify its name to Configure. 7.5 Why does lsof indicate incomplete paths with " -- " for Tru64 UNIX 5.1 files? When lsof can't find a component of a path in the kernel's name cache (aka DNLC), or can't determine that the left-most component has as its parent the file system root, it uses an "incomplete path" notation. That notation begins with the file system root name, followed by " -- ", followed by the consecutive path name components lsof was able to find in the DNLC -- e.g., "/ -- init". Because the DNLC was significantly redesigned in Tru64 UNIX 5.1, lsof's handling of the cache had to be completely redone. As part of the DNLC redesign a name cache entry parameter lsof formerly used to locate the file system root of a path was removed. With help from Chang Song I've been able to implement an alternate method for detecting the root of these file system types: AdvFS (MSFS), CDFS, DVDFS, FDFS, NFS, NFS3, and UFS. When lsof doesn't know how to identify the root for a file system type, it will resort to the " -- " incomplete path notation. 7.6 Why doesn't lsof report link count, node number, and size for some Tru64 5.x CFS files? Lsof reports link count, node number, and size for open CFS files as recorded in their kernel node structure's cached attributes. Sometimes not all attributes are cached on the system where lsof runs, so lsof cannot report them. 7.7 Why does lsof say it can't read the kernel name list or proc table on Digital UNIX 4.x or Tru64 UNIX? By default on Digital UNIX 4 and Tru64 UNIX lsof reads the addresses for kernel symbols with the knlist(3) function. That function can fail, for example, when the kloadsrv daemon isn't running or is malfunctioning. When that happens, lsof may abort with one of these error messages: lsof: can't read kernel name list from knlist(3): ... or lsof: can't read proc table info The first message suggests a complete knlist(3) or kloadsrv failure; the second, a partial one. If you know the name of the file from which the running system was booted, e.g., /vmunix, you can use lsof's -k option to direct it to read kernel symbol addresses from the name list of that file -- $ lsof -k /vmunix ... If that works, then knlist(3) is malfunctioning and you need to fix it. 8.0 FreeBSD Problems 8.1 Why doesn't lsof report on open kernfs files? Lsof doesn't report on open FreeBSD kernfs files because the structures lsof needs aren't defined in the kernfs.h header file in /sys/misc/kernfs. 8.2 Why doesn't lsof work on my FreeBSD system? If lsof doesn't work on your FreeBSD system, first make sure you have the latest lsof revision. See the answer to the "Where do I get lsof?" question for information on how to get the latest lsof revision. Once you have gotten the latest lsof revision, Configure and make it. If Configure fails -- e.g., it complains about an unknown FreeBSD version -- then lsof probably hasn't been ported to your FreeBSD version yet, and there's no need to go any further. Follow the answer to the "How do I report an lsof bug" to report the Configure complaint to me. If you are able to Configure and make lsof, run its test suite. (See the answer to the "Is there a test suite?" question for more information on how to use lsof's test suite.) If lsof still fails, make sure your kernel sources, kernel header files, kernel boot file, standard header files and libraries are synchronized. They should all be built from the same CVS refresh. If they aren't, then the KVM library or lsof may be using kernel structure definitions that don't match the booted kernel. If you have synchronized your kernel, header files and libraries, and still can't get lsof to work, follow the steps in the answer to the "How do I report an lsof bug" question to report the problem to me. 8.3 Why doesn't lsof work on the RELEASE version of CURRENT? Lsof tracks the CURRENT release of the current leading edge FreeBSD version, because my access to leading edge FreeBSD is limited to FreeBDSD.org reference systems, all running the CURRENT release. Sometimes that tracking leads to changes in lsof that won't work on an earlier RELEASE version of the current leading edge version. When that happens, please send e-mail to me <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 8.4 Why does kvm_open() complain it can't find some file? If lsof issues this complaint: lsof: kvm_open(execfile=/boot/kernel/kernel, corefile=/dev/mem: No such file or directory Your FreeBSD system might not have a /dev/mem device. If not, create one -- e.g., as root do: # mknod /dev/mem c <major> 0 # chmod 440 /dev/mem # chgrp kmem /dev/mem For <major> use /dev/kmem's major device number. You may have to run kldload, too -- again as root do: # kldload mem 8.5 FreeBSD ZFS Problems 8.5.1 Why does FreeBSD lsof report "WARNING: no ZFS support has been defined."? Lsof issues that message when it detects a file on a ZFS file system, but has not been built with support for ZFS. Lsof's Configure script detects support can be added for ZFS when it finds this file: /usr/src/sys/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_znode.h That header file and others in the OpenSolaris files in /usr/src enable lsof to extract information about ZFS files from the kernel structures associated with them. 8.6 Why can't Configure create lsof_owner.h for FreeBSD 6 and above? Lsof may report: Creating ./lockf_owner.h from /usr/src/sys/kern/kern_lockf.c FATAL ERROR: can't read /usr/src/sys/kern/kern_lockf.c FATAL ERROR: ./lockf_owner.h creation failed (see 00FAQ) or Creating ./lockf_owner.h from /usr/src/sys/kern/kern_lockf.c FATAL ERROR: ./lockf_owner.h creation failed (see 00FAQ) Those messages mean that lsof's Configure script failed to create a local header file, ./lockf_owner.h, needed to use the new kernel file locking code of some versions of FreeBSD 6 and above. The changes that implement that new locking code alter the lockf structure in <sys/lockf.h> and introduce a new structure, lockf_entry, to that header file. When Configure detects the presence of the lockf_entry definition in <sys/lockf.h>, it tries to construct the local header file, ./lockf_owner.h. Configure has to do that because an unfortunate side effect of the new kernel file locking code is that <sys/lockf.h> doesn't contain the lockf_owner structure definition referenced in its own lockf structure. Lsof needs to access elements of that lockf_owner structure to determine if a lock belongs to the process that has a file open. The missing lockf_owner structure definition is in the kernel source file, typically /usr/src/sys/kern/kern_lockf.c. Configure tries to extract the lockf_owner structure definition from kern_lockf.c into lsof's local header file, ./lockf_owner.h. If Configure can't do that, it reports: FATAL ERROR: ./lockf_owner.h creation failed If Configure can't even read kern_lockf.c, it first reports: FATAL ERROR: can't read /usr/src/sys/kern/kern_lockf.c The work-around for this problem is to update the FreeBSD kernel /usr/src tree (e.g., do a CVSup or csup) on the system where lsof is to be built and then do a "make buildworld" followed by a "make installworld". 8.6.1 Why are there lockf structure compiler errors for FreeBSD 6.0 and higher lsof? If, when compiling lsof, the compiler complains with error messages like: dnode.c: In function 'get_lock_state': dnode.c:113: error: 'struct lockf' has no member named 'lf_flags' dnode.c:115: error: 'struct lockf' has no member named 'lf_id' ... Then lsof is being built on a system that has new kernel file locking code and lsof's Configure script failed to build a local lockf_owner.h header file with a structure definition lsof needs. See the "Why can't Configure create lsof_owner.h for FreeBSD 6 and above?" section for more information and a work-around. 8.6.2 Why don't /usr/src/sys/sys/lockf.h and /usr/include/sys/lockf.h match? This mismatch can cause the errors explained in the answer to the "Why are there lockf structure compiler errors for FreeBSD 6.0 and higher lsof?" question. If /usr/src/sys/sys/lockf.h has been updated with a CVSup or csup, the new lockf.h won't be propagated to /usr/include/sys until the "make buildworld" and "make installworld" steps have been completed. 9.0 HP-UX Problems 9.1 What do /dev/kmem-based and PSTAT-based mean? Lsof for HP-UX 11.0 and below uses /dev/kmem to read kernel data structures from which it gathers and reports open file information. That version of lsof is called /dev/kmem-based lsof. Starting with HP-UX 10.10, finding definitions for the necessary kernel structures became more difficult as HP no longer distributed header files in /usr/include that defined all kernel structures. So I started "inventing" structure definitions by using Q4 to display them. By HP-UX 11, the process of invention became extremely intensive to support. Following a patch to the ipc_s structure in early 1999, my invented definition of that structure became incorrect. Although I was able to devise a work-around test for the patch with Q4, it was clear that my inventions were bound to cause more problems. Discussion with HP about the patch led to my proposing that an lsof API in the HP-UX kernel was the proper solution. Much to my surprise, HP agreed. I believe Carl Davidson was the prime mover behind that decision, but I know others participated, among them Louis Huemiller, Rich Rauenzahn, and Sailu Yallapragada. I am indebted to these folks and HP for their willingness to do this work. The API was added to the PSTAT interface in a project named PEGL, Pstat Enhancements for Glance and Lsof. Louis and Sailu did the bulk of the design and implementation work and testing began in March, 2000 HP-UX 11.11 is the first version that provides PSTAT support for lsof. HP-UX versions in between 11.0 and 11.11 -- all Beta versions as far as I can determine -- have no lsof support. See the "PSTAT-based HP-UX lsof Questions" section for questions and answers specific to PSTAT-based HP-UX lsof. The next section, "Why doesn't a /dev/kmem-based HP-UX lsof compilation use -O?" covers /dev/kmem-based HP-UX lsof. The /dev/kmem-based lsof sources may be found in the kmem subdirectory of the dialects/hpux branch of the lsof source tree. The PSTAT-based lsof sources may be found in .../dialects/hpux/pstat. 9.2 /dev/kmem-based HP-UX lsof Questions The sources for /dev/kmem-based lsof for HP-UX may be found in lsof_<revision>/dialects/hpux/kmem. Lsof's Configure shell script decides to use these sources when it finds that the /usr/include/sys/pstat subdirectory doesn't exist. Lsof can be forced to use the /dev/kmem sources by setting "/dev/kmem" in the HPUX_BASE environment variable. Consult the Configure shell script and 00XPORTING for more information. 9.2.1 Why doesn't a /dev/kmem-based HP-UX lsof compilation use -O? If you only have the standard (bundled) HP-UX C compiler and haven't purchased and installed the optional one, then you can't use cc's -O option. The HP-UX cc(1) man page says this: "Options Note that in the following list, the cc and c89 options -A , -G , -g , -O , -p , -v , -y , +z , and +Z are not supported by the C compiler provided as part of the standard HP-UX operating system. They are supported by the C compiler sold as an optional separate product." Lsof's Configure script tries to detect what C compiler product you have installed by examining your compiler. If that examination reveals a standard (bundled) compiler, lsof avoids using -O. If the Configure compiler test fails, the C compiler will complain that it doesn't support -O. You can suppress that complaint with this make invocation: $ make DEBUG="" 9.2.2 Why doesn't the /dev/kmem-based CCITT support work under 10.x? Pasi Kaara, who originally provided the HP-UX CCITT support, reports that it no longer works under HP-UX 10.x. Consequently, at lsof revision 4.02 it has been disabled. 9.2.3 Why can't /dev/kmem-based lsof be compiled with `cc -Aa` or `gcc -ansi` under HP-UX 10.x? Some HP-UX 10.x header files, needed by lsof, can't be compiled properly in ANSI_C mode; structure element definition and alignment problems result. The f_offset member of the file structure, for example, is incorrect. This ANSI-C obstacle extends to using the -Aa option of the HP C compiler and the -ansi option of gcc. 9.2.4 Why does /dev/kmem-based lsof complain about no C compiler? Lsof's Configure script looks in /bin and /usr/ccs/bin for an HP C compiler, because it needs to know if the compiler is the standard (bundled) one or the optional separate product. If it finds no compiler in either place, Configure quits after complaining: No executable cc in /bin or /usr/ccs/bin If you don't have a C compiler in either of these standard places, you should consider installing it. If you have gcc installed, you can use it by declaring the ``hpuxgcc'' abbreviation to lsof's Configure script. If you have a C compiler in a non-standard location, you can use the HPUX_CCDIR[12] environment variables to name the path to it. Consult the 00XCONFIG file of the lsof distribution for more information. 9.2.5 Why does Configure complain about q4 for /dev/kmem-based lsof for HP-UX 11? When you run Configure on an HP-UX 11 system, it may complain: !!!ERROR!!! !!!ERROR!!! !!!ERROR!!! !!!ERROR!!! Configure can't use /usr/contrib/bin/q4 to examine the ipis_s structure. You must do that yourself, report the result in the HPUX_IPC_S_PATCH environment variable, then repeat the Configure step. Consult the Configure script's use of /usr/contrib/bin/q4 and the 00XCONFIG file for information on ipis_s testing and the setting of HPUX_IPC_S_PATCH. !!!ERROR!!! !!!ERROR!!! !!!ERROR!!! !!!ERROR!!! This message states that Configure cannot use q4 from /usr/contrib/bin to examine the kernel's boot image for the ipis_s structure. Maybe q4 hasn't been installed, or perhaps Configure can't execute it. Lsof needs to gather information about ipis_s to determine if the ipis_s structure is defined in the kernel boot image, if the ipis_s structure of the kernel boot image has an ipis_msgsqueued member, and if the ipc_s structure of the kernel boot image uses has an ipc_ipis member. The ipis_s structure isn't described in any header file HP-UX releases with HP-UX 11. It appears in the private lsof header file .../dialects/hpux/kmem/hpux11/ipc_s.h. Lsof gets local and remote connection addresses (IP and port numbers) from ipc_s, so an incorrect ipc_s definition may cause incorrect reporting of TCP/IP connection addresses. It definitely will cause incorrect reporting on 32 bit kernels. In any case lsof should be compiled with a correct ipc_s definition no matter the kernel bit size, so the Configure script always tests for it when the HP-UX version is 11. For lsof's Configure script to gather the necessary ipis_s information q4 needs to be installed in /usr/contrib/bin and the kernel boot image, /stand/vmunix, needs to have been processed with pxdb. If either is untrue, lsof issues the above error message, perhaps preceded by q4 messages. (Note: lsof's use of q4 may also fail if q4 can't execute nm -- e.g., it can't find /usr/bin/nm, or there is a conflicting, private version of nm earlier in the path.) If /stand/vmunix hasn't been processed by pxdb, the q4 messages will include: q4: (error) vmunix not pxdb'd or q4: (warning) /stand/vmunix has not been processed by pxdb. It's possible to make a suitable private copy of /stand/vmunix for configuring lsof. That requires /opt/langtools/bin/pxdb or the q4 version of pxdb from /usr/contrib/bin/q4pxdb. The path to the result is supplied to the lsof Configure script in the HPUX_BOOTFILE environment variable. Configure still requires /usr/contrib/bin/q4. The following sample Bourne shell commands make a private copy of /stand/vmunix in /tmp, process it with pxdb or q4pxdb, and supply its path to lsof's Configure script in HPUX_BOOTFILE. $ cp /stand/vmunix /tmp/vmunix.lsof $ /opt/langtools/bin/pxdb /tmp/vmunix.lsof or $ /usr/contrib/bin/q4pxdb /tmp/vmunix.lsof ... pxdb messages ... $ HPUX_BOOTFILE=/tmp/vmunix.lsof Configure -n hpux It may also be necessary to use q4 outside the lsof Configure script. In that case q4 can be to determine the state of ipis_s and ipc_s with these q4 commands: $ /usr/contrib/bin/q4 /stand/vmunix ... q4> fields -c struct ipc_s ... q4> fields -c struct ipis_s Look in the q4 output for the ipc_ipis member of the ipc_s structure, and look in the q4 output for the ipis_s structure for the ipis_msgsqueued member. If ipc_s has ipc_ipis but ipis_s lacks ipis_msgsqueued, set HPUX_IPC_S_PATCH environment variable to "1". If ipc_s has ipc_ipis and ipis_s has ipis_msgsqueued, set HPUX_IPC_S_PATCH to "2" -- e.g., $ HPUX_IPC_S_PATCH=1 Configure -n hpux or $ HPUX_IPC_S_PATCH=2 Configure -n hpux If ipc_s has no ipc_ipis member, set HPUX_IPC_S_PATCH to "N" -- e.g., use this Configure step: $ HPUX_IPC_S_PATCH=N Configure -n hpux 9.2.6 When compiling /dev/kmem-based lsof for HP-UX 11 what do the "aCC runtime: ERROR..." messages mean? When the lsof Makefile asks the HP-UX unbundled compiler to load lsof, it may complain: /bin/cc -o lsof -DHPUXV=1100 -DHASVXFS -DHPUXKERNBITS=64 \ -I/home/abe/src/lsof4/dialects/hpux/kmem/hpux11 +DD64 \ -DHAS_IPC_S_PATCH=2 -I/home/abe/src/lsof4/dialects/hpux/kmem \ -DLSOF_VSTR=\"B.11.00\" -g dfile.o dmnt.o dnode.o dnode1.o \ dnode2.o dproc.o dsock.o dstore.o arg.o main.o misc.o \ node.o print.o proc.o store.o usage.o -L./lib -llsof -lelf \ -lnsl aCC runtime: ERROR: Unexpected use of shared libraries aCC runtime: ERROR: Read aCC manpage, +A option /usr/lib/nls/loc/locales.1//is_IS.iso88591 This is a bug in the HP-UX national language support. (Notice the last message with "locales" in it?) Complain to HP -- then use this work-around before executing make: $ unset LANG $ make 9.2.7 Why doesn't /dev/kmem-based lsof for HP-UX 11 report VxFS file link counts, node numbers, and sizes correctly? This is usually the result of running an lsof binary whose revision number is less than 4.57 on a system that has OnlineJFS support installed. It can also happen with lsof 4.57 binaries when the OnlineJFS support with which they were built doesn't match the OnlineJFS status of the system on which they are run. The OnlineJFS status of lsof 4.57 and higher binaries can be determined by running: $ lsof -v 2>&1 | grep HASONLINEJFS If that shell pipe produces output, lsof was compiled with OnlineJFS support enabled; no output, disabled. If OnlineJFS is installed on an HP-UX 11 system the /sbin/fs/vxfs/subtype executable exists and outputs "vxfs3.3" when run. The problem occurs because the optional OnlineJFS support installation doesn't update <sys/fs/vx_inode.h>. Consequently lsof can be compiled with an incorrect definition of the vx_inode structure and look for for link counts, node numbers, and sizes in the wrong places in the structure. The current response I have gotten from HP is that no <sys/fs/vx_inode.h> update will be provided for OnlineJFS. I've addressed this problem temporarily with a work-around (hack) in lsof revision 4.57. 9.2.8 Why can't /dev/kmem-based lsof be built with gcc for 64 bit HP-UX 11? When Configure is given the "hpuxgcc" abbreviation, the HP-UX version is 11, and the kernel bit size is 64, the lsof Configure script may abort with the messages: !!!!!!!!!!!!!!!!! FATAL ERROR !!!!!!!!!!!!!!!!!! APPARENTLY GCC CANNOT BUILD 64 BIT EXECUTABLES. A COMPILER MUST BE USED THAT CAN. SEE 00FAQ FOR MORE INFORMATION. (This is the "more information" in 00FAQ.) This means the Configure script compiled a test program with gcc the result wasn't an ELF-64 binary. Lsof tries two gcc modes, one with no options and another with the -mlp64 option, before it concludes gcc can't be used. See the "How can I acquire a gcc for building lsof for 64 bit HP-UX 11?" answer for information on where you might be able to get a gcc for HP-UX 11 that can produce ELF-64 executables. 9.2.8.1 How can I acquire a gcc for building lsof for 64 bit HP-UX 11? Check this HP URL: http://h21007.www2.hp.com/dspp/tech/tech_TechSoftwareDetailPage_IDX/1,1703,547,00.html (That's one very long link; be careful you cut 'n paste it all.) In November 2001 that URL led to a web page whose title was "gcc for hp-ux 11." The page offered a link for downloading a 64 bit gcc 3.0 compiler for HP-UX 11.0 and 11i. Rich Rauenzahn of HP installed that compiler on an HP test system he allows me to use and I successfully built a 64 bit lsof with it. The HP package may install the 64 bit capable gcc in /usr/local/pa20_64/bin/gcc, so you may have to adjust your path or set the LSOF_CC environment variable to compensate. 9.2.9 Why does /dev/kmem-based lsof for HP-UX 11 report "unknown file system type" for some open files? The lsof binary being used probably doesn't have support for the VxFS file system. To confirm that, check `lsof -v` output for "-DHASVXFS". If it's not present, lsof doesn't have VxFS support. You also need to establish that lsof really is complaining about VxFS files by checking the kernel boot file for the symbol associated with the hexadecimal address reported in the "unknown file system type" message -- e.g., "v_op: 0x8711c8." Use nm(1) to do that: $ nm -x /stand/vmunix | grep 8711c8 If nm reports the symbol associated with the address is vx_vnodeops, then lsof is complaining about an open VxFS file. The solution in that case is to build lsof yourself (The bundled C compiler will do it.), making sure that lsof's Configure script detects the presence of VxFS. Configure does that by finding these two header files: /usr/include/sys/fs/vx_hpux.h /usr/include/sys/fs/vx_inode.h If the system where you are building lsof doesn't have those header files, but does have VxFS, you might be able to install the header files by installing the HP JournalFS package from the CoreOS CD -- in particular the file set JournalFS.VXFS-PRG and its associated patch, PHKL_18543. (My thanks to Steve Bonds for that information.) Finally, if you find that lsof isn't complaining about VxFS when it complains about an unknown file system type, send e-mail to me <abe@purdue.edu> for further assistance. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 9.2.10 Why does the ANSI-C compiler complain about comments in HP-UX 11 header files? When compiling lsof on HP-UX 11, the HP ANSI-C compiler's pre-processor, cpp, may complain about comments in HP-UX header files -- e.g., cpp: "/usr/include/sys/cdfs.h", line 232: warning 2028: Found comment inside comment started on line 232. cpp: "/usr/include/sys/cdnode.h", line 196: warning 2028: Found comment inside comment started on line 196. cpp: "/usr/include/nfs/snode.h", line 30: warning 2028: Found comment inside comment started on line 30 This is not a problem with lsof. It is a problem with the HP-UX header files; they have non-compliant ANSI-C comment sequences in them -- e.g., <sys/cdfs.h>: 232 /* struct cdfs *cdfs_link; /* linked list of file systems */ The initial "/*" is not terminated by an ending "*/" before the appearance of a second "/*". 9.2.11 Why does dnode1.c cause the HP-UX 11 compiler to complain that <sys/fs/vx_inode.h> is missing or incorrect? If CFLAGS in the lsof Makefile for an HP-UX 11 compilation includes HASONLINEJFS, indicating the system has OnlineJFS support, lsof needs the <sys/fs/vx_inode.h> header file. Sometimes it is missing from /usr/include/sys/fs. <sys/fs/vx_inode.h> is a header file that must be obtained from Veritas. If that proves impossible, please contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 9.3 PSTAT-based HP-UX lsof Questions The sources for PSTAT-based lsof for HP-UX may be found in lsof_<revision>/dialects/hpux/pstat. Lsof's Configure shell script decides to use these sources when it finds that the /usr/include/sys/pstat subdirectory exists. Lsof can be forced to use the PSTAT-based sources by setting "pstat" in the HPUX_BASE environment variable. Consult the Configure shell script and 00XPORTING for more information. 9.3.1 Why does PSTAT-based lsof complain about pst_static and other PSTAT structures? When lsof starts it may issue one of these fatal error messages: lsof: FATAL: can't determine PSTAT static size lsof: FATAL: can't read <n> bytes of pst_static lsof: FATAL: pst_static doesn't contain <name>_size lsof: FATAL: <name>_size should be <n> These messages indicate that lsof's tests for the proper level of PSTAT support have failed. The structure names, given in <name>, and sizes, given in <n>, identify the support deficiency more precisely. You may need to upgrade the PSTAT support in your kernel to be able to use PSTAT-based lsof. 9.3.2 Why does PSTAT-based lsof complain it can't read pst_* structures? Lsof may put messages like the following in the NAME column of its output. can't read cwd pst_filedetails: Permission denied can't read mem pst_filedetails: Permission denied can't read rtd pst_filedetails: Permission denied can't read txt pst_filedetails: Permission denied can't read pst_filedetails: Permission denied can't read 3 stream structures: Permission denied can't read pst_socket: Permission denied These messages indicate that the lsof binary lacks the authority to read the name structures for processes other than ones belonging to the UID under which lsof is running. Authority to read the structures of other processes is limited to root processes -- i.e., lsof must have setuid-root permission if it is to list open files for arbitrary processes. If you want to eliminate these errors, you must run lsof as root or install it with setuid-root permission. 9.3.3 Why does PSTAT-based lsof rebuild the device cache file after each reboot? After each HP-UX rebuild, the first time a user runs lsof it will report: lsof: WARNING: device cache mismatch: /dev/tun... lsof: WARNING: created device cache file: /<user_path> This happens because the device numbers on /dev/tun* device nodes are recalculated at each reboot. When lsof detects a change in the device number of a /dev/tun* file, it rebuilds its local device cache file. 9.3.4 Why doesn't PSTAT-based lsof report TCP addresses for telnetd's open socket files? When lsof can't report TCP addresses for telnetd's open socket files it is because an unpatched PSTAT kernel interface doesn't report the addresses to lsof. This has been addressed in PSTAT kernel patch PHKL_24047. It is available from the HP IT Resource Center at: http://itrc.hp.com In the page's "maintenance / support" box select the "individual patches" link. Once at its page, select the "hp-ux" link. On that page select the "Series 800" or "Series 700" radio button and select "11.11" from the pull-down list to the right of the button. Under "search or browse the path list" select "Search by Patch IDs" from the pull down list, enter PHKL_24047 in the following text box, and select search. That should lead to information about PHKL_24047 and a link for downloading it. (You may have to log in first and you may have to create a login identity by registering before you can log in.) Some time in March 2006 the PHKL_24047 patch was "lost" by the HP-UX networking lab. It has been "found" again in August 2006 and will be re-released as a GRO patch "some time." I don't yet know when that will be. You must contact HP to learn about the availability of the GRO patch. 9.3.5 Why does PSTAT-based lsof cause an HP-UX 11.11 kernel panic? When PSTAT-based lsof runs on some HP-UX 11.11 kernels, the kernel may panic. Symptoms include: Console message: 0xFBE000301100EF00 00000000 0000EF00 - type 31 = legacy PA HEX chassis-code /var/adm/syslog: ... vmunix: Trap Type 15 (Data page fault) ... vmunix: Instruction Address (pcsq.pcoq) = 0x... The panic is caused by a bug in the way PSTAT's pstat_getstream() function obtains module names from streams managed by the otsam stream driver (part of OSI Transport Services). Lsof calls pstat_getstream() when it encounters an open otsam stream file. An HP-UX 11.11 system uses otsam if otsam appears in /stand/system. HP-UX 11.11 patch PHKL_24507 (available some time after July 15, 2001) fixes the pstat_getstream() bug. See the information in the answer to the "Why doesn't PSTAT-based lsof report TCP addresses for telnetd's open socket files?" question for information on how to obtain the patch. 9.3.6 Why doesn't PSTAT-based lsof report a CWD that is on a loopback (LOFS) file system? When PSTAT-based lsof reports on processes whose current working directory (CWD) is on a loopback file system, lsof can't report the open CWD file. The reason is that the HP-UX 11.11 and above kernel's loopback file system code is not passing the CWD file ID to the kernel's pstat(2) code. Hence lsof is given no information on the lofs CWD. The problem was first reported to me by Ermin Borovac and an internal bug report was filed with the HP-UX file system group on October 26, 2004. That report has now been answered by the patch PHKL_33200 -- s700_800 11.11 lofs cumulative patch. The HP IT Resource Center (http://itrc.hp.com) is a source for the patch. 9.3.7 Why do some swinstall packages for PSTAT-based HP-UX 11.11 packages complain about setgid and setuid bits? First, let me explain that I do not provide lsof swinstall packages for lsof. Others provide them and they should be contacted about problems with their packages. However, I have become aware of a problem with one package about which I have some information I can share. The problem shows up in these swinstall messages: ERROR: Unknown owner and/or group for file "/usr/local/bin/lsof". SUID and/or SGID bit was not set. ERROR: Failed installing fileset "lsof.lsof-RUN,r=4.73". Check the above output for details. The swpackage SUID/SGID functionality was restricted by changes for POSIX compliance, breaking backward compatibility. The patch PHCO_27671 allows SUID/SGID for uid/gid of 0 only, as a compromise between backward compatibility and POSIX conformance. If the setuid bit is to be set on the executable, the UID and GID of the executable must be 0 (zero). 9.3.8 Why won't the bundled C compiler build PSTAT-based lsof for PA-RISC HP-UX 11.23? A PA-RISC HP-UX 11.23 bundled C compiler dated May 2005 or later will not build PSTAT-based lsof. It will deliver error messages related to the system's <gssapi/gssapi.h> header file. There is nothing wrong with that header file or lsof. The problem is that the bundled C compiler can't cope with the gssapi.h header file. The work-around is to use the HP ANSI C compiler. Using gcc is not a satisfactory work-around. See the answer to the "Why won't gcc build PSTAT-based lsof for PA-RISC HP-UX 11.23?" question for more information. 9.3.9 Why won't gcc build PSTAT-based lsof for PA-RISC HP-UX 11.23? Gcc will not even compile PSTAT-based lsof revisions below 4.77 for PA-RISC HP-UX 11.23 dated May 2005 or later. It reports errors in lsof's print.c fill_portmap() function about missing members of the rpcent structure. That happens because gcc defines _XOPEN_SOURCE_EXTENDED which disables the definition of the rpcent structure in <netdb.h>. Using the HP bundled C compiler is not a viable work-around. That is explained in the answer to the "Why won't the bundled C compiler build PSTAT-based lsof for PA-RISC HP-UX 11.23?" While an lsof revision 4.77 or higher can be compiled with gcc, the results are unreliable. Lsof will compile, but it occasionally produces segment faults when it runs. I have not been able to reproduce the failure reliably or locate a debugger that will work with the gcc-compiled lsof. The only reliable work-around is to use the HP ANSI C compiler. 9.3.10 Why does PSTAT-based lsof complain, "FATAL: pst_stream_size should be: 672; is 72" on HP-UX 11.11 and above? This message indicates a mismatch between the PSTAT header files used to build lsof (<sys/pstat.h> and those in the /usr/include/sys/pstat subdirectory), and those that built the running kernel. Unfortunately the June 2008 patch set for HP-UX 11.23 creates this inconsistency, because it does not contain all the patches needed to match the kernel with the PSTAT header files. Even more serious is that the missing patches update the kernel's PSTAT support to provide TCP/UDP endpoint information to lsof from TCP/TLI streams. The patch inconsistency comes about because, while the following patch is installed, PHKL_36577 1.0 PM-PSTAT section 2 manpage changes other kernel patches are not. The PHKL_36577 patch updates the PSTAT header files and manual pages to match kernel changes that other patches with the following numbers (or patches that contain or supersede them) contain: PHNE_36575 1.0 Cumulative STREAMS Patch PHNE_37670 1.0 cumulative ARPA Transport patch PHNE_37851 1.0 NFS cumulative patch Those patches implement the kernel changes that support the delivery of information promised in patch PHKL_36577. The work-around is to install the missing patches. 9.4 Why won't the HP-UX depot install? I don't distribute lsof depts, so I can't support them. From time to time depots prepared by various sites -- e.g., usually HP-UX software collection sites -- will contain errors that cause installation of the depot to fail. Do not contact me when this happens. Instead, contact the administrator of the site that prepared the depot. As should be clear from the bulk of the lsof documentation, I do not recommend you use pre-built lsof binaries in any form. Instead, I recommend you obtain the lsof source distribution and build lsof yourself. 10.0 Linux 10.1 What do /dev/kmem-based and /proc-based lsof mean? At approximately Linux 2.1.72 and exactly at lsof revision 4.23 support for Linux forks. The first fork, containing the oldest lsof form is based on access to kernel memory structures, and is called /dev/kmem-based lsof. A /dev/kmem-based lsof is heavily intertwined with the Linux kernel version, its header files, and its system map file. Typically a /dev/kmem-based lsof needs only setgid permission to local all open file information. After approximately Linux 2.1.72 and at revision 4.23 lsof obtains all its information from the /proc file system. That lsof is called the /proc-based lsof. A /proc-based lsof does not read kernel memory, needs neither kernel header files nor the system map file, and is less likely to be affected by Linux kernel changes. However, it does require setuid-root permission to list all open files, and it can't report file offsets (positions). After revision 4.52 the /dev/kmem-based Linux sources for lsof are no longer distributed. Information about them may be found in the 00INDEX and README files at: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/OLD/src 10.2 /proc-based Linux lsof Questions 10.2.1 Why doesn't /proc-based lsof report file offsets (positions)? /proc-based lsof revisions 4.79 and above can only report file offsets (positions) for the files of Linux kernels 2.6.22 and above. During its initialization /proc-based lsof tests to see if offset information can be obtained. If it cannot, lsof disables offset reporting. If the -o option was selected, lsof also issues this warning: lsof: WARNING: can't report offset; disregarding -o. 10.2.2 Why does /proc-based lsof report "can't identify protocol" for some socket files? /proc-based lsof may report: COMMAND PID ... TYPE ... NODE NAME pump 226 ... sock ... 309 can't identify protocol This means that it can't identify the protocol (i.e., the AF_* designation) being used by the open socket file. Lsof identifies protocols by matching the node number associated with the /proc/<PID>/fd entry to the node numbers found in selected files of the /proc/net sub-directory. Currently /proc-based lsof examines these protocol files: /proc/net/ax25 (untested) /proc/net/ipx (needs kernel patch) /proc/net/raw /proc/net/raw6 /proc/net/tcp /proc/net/tcp6 /proc/net/udp /proc/net/udp6 /proc/net/unix If /proc-based lsof says it can't identify the protocol for an open socket file, you may be able to identify the protocol yourself by using grep to look for the specific node number in the files of /proc/net -- e.g., $ grep <node_number> /proc/net/* You may not be able to find the desired node number, because not all kernel protocol modules fully support /proc/net information. If you find a matching node number in a /proc/net file that is not currently being processed by lsof, contact me via e-mail at <abe@purdue.edu>. I'll discuss adding support to /proc-based lsof for the protocol of the /proc/net file with you. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. The code that matches node numbers of open IPX protocol socket files to those in /proc/net/ipx requires Jonathan Sergent's Linux 2.1.79 patch to /usr/src/linux/net/ipx/af_ipx.c. The patch, suitable for input to Larry Wall's patch program, may be found in the lsof distribution file: .../dialects/linux/proc/patches/net_ipx_af_ipx.c.patch 10.2.3 Why does /proc-based lsof warn about unsupported formats? Lsof may issue the following warning: lsof: WARNING: unsupported format: /proc/net/<file> if the header line of the indicated <file> in /proc/net -- ax25, ipx, raw, tcp, udp, or unix -- doesn't match what lsof expects to find. When the header line of a /proc/net file isn't what lsof expects, lsof probably can't parse the rest of the file correctly and doesn't try. As a result, lsof can't report any NAME column information (e.g., local and remote addresses) for socket files bound to the indicated network protocol. If you get this warning, please send me e-mail at <abe@purdue.edu>. Include the contents of the file lsof claims has an unsupported format. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 10.2.4 Why does /proc-based lsof report "(deleted)" after a path name? The "(deleted)" notation following a path name in /proc-based lsof's NAME column comes from the /proc/<PID>/fd/<FD> entry for the open file. It's the Linux kernel's way of indicating the file is open but has been unlinked (rm'd). 10.2.5 Why doesn't /proc-based lsof report full open file information for all processes? /proc-based lsof can only report on processes whose /proc files it has permission to read. /proc normally grants permission to read all its files only to root or to the owning user ID. Without permission to read most /proc files, lsof can only report full information for processes belonging to the user who is running lsof. /proc-based lsof may be able to report some information for all processes, depending on the permissions of their associated /proc files, but usually /proc-based lsof won't be able to access the files in /proc/<PID>/fd/ that describe regular open files. If you want /proc-based lsof to report on all processes, you must install it with setuid-root permission. 10.2.6 Why won't Customize offer to change HASDCACHE or WARNDEVACCESS for /proc-based lsof? /proc-based lsof doesn't read device information from /dev or the device cache file, so it makes no sense to change the state of device cache processing or /dev node accessibility warnings. 10.2.7 /proc-based lsof Linux NFS questions 10.2.7.1 Why can't lsof find files on an accessible NFS file system? On occasion lsof may be unable to identify that an open file is on an NFS file system. This is most likely the result of a bug in the way the Linux kernel supplies information to the reader of /proc/mounts (lsof) -- sometimes that pseudo-file is truncated by the kernel. One way to see if this is the case is to search for the NFS file system in /proc/mounts -- e.g., $ grep <NFS_file_system_mount_point> /proc/mounts If you get no output or the third word of the output isn't "nfs", then lsof won't consider the file system an NFS file system. A second test is to look at the end of /proc/mounts -- e.g., $ tail /proc/mounts If tail reports "# truncated" then /proc/mounts is incomplete because of a Linux kernel bug. The bug is documented at: http://www.xss.co.at/sysinfo/mounts.html The bug is fixed in Linux kernel 2.4.18, and possibly in some earlier Linux kernel versions. 10.2.7.2 Why can't lsof find files on an inaccessible NFS file system? If lsof issues this message about a Linux file system, mounted from an NFS server: lsof: WARNING: can't stat() nfs file system /xxx/yyy Then lsof won't be able to find any open files on the file system. That's because of an inadequacy in the Linux /proc file system. Its /proc/mounts file doesn't give the device doublet (major and minor numbers) of the file system as do many UNIX systems (e.g., Solaris). The only way lsof can get the device doublet for a Linux file system is to call stat(2) on the file system path, which fails if the NFS server isn't accessible. When lsof doesn't know the device doublet of a file system, it can't find open files on the inaccessible file system, because it can't match the doublets of open files to the doublet of the inaccessible file system. This topic is covered extensively in lsof(8) it its ALTERNATE DEVICE NUMBERS and BLOCKS AND TIMEOUTS sections. 10.2.8 Why doesn't /proc-based Linux lsof report socket options and values, socket state flags, and TCP options and values? The Linux /proc file system doesn't report socket options and values, socket states, and TCP options and values to lsof. 10.2.9 Does /proc-based Linux lsof use a device cache? No. The Linux /proc/<PID>/fd/* entries provide device names to lsof via readlink(2). It is not necessary to enable device cache processing for /proc-based Linux lsof via the Customize script or modifications to the Linux machine.h header file. 10.2.10 Why doesn't /proc-based Linux lsof report any or all file structure values for its +fcfgGn option? /proc-based lsof revisions 4.79 and above can only report some file structure values for Linux kernels below 2.6.22. When running on Linux kernels at 2.6.22 and above lsof 4.79 can report some file flag values -- i.e., in response to the +fg or +fG options. The flag values are obtained from the /proc/<PID>/fdinfo/ files introduced at Linux kernel 2.6.22. /proc-based Linux lsof tests its availability to obtain file flag values at initialization. If values are not available, lsof disables file flag reporting. If the flags were requested with +fg or +fG, lsof displays this warning: lsof: WARNING: can't report file flags; disregarding +f. As a special note, when Linux lsof can report flag bits, it will not report 'R' for a read-only file. There is no read-only flag bit O_* symbol in <fcntl.h> (or <bits/fcntl.h>) and lsof reports only bits that are set. The absence of O_RDWR and O_WRONLY flag bits implies the file is read-only. 10.3 Special Linux file types 10.3.1 Why is ``DEL'' reported as a Linux file type? Lsof usually reports entries from the Linux /proc/<PID>/maps file with ``mem'' in the TYPE column. However, when lsof can't stat(2) a path in the process' ``maps'' file and the ``maps'' file entry contains ``(deleted)'', indicating the file was deleted after it had been opened, lsof reports the file type as ``DEL''. 10.3.2 Why is ``unknown'' reported as a Linux file type? Lsof may report a Linux file's type as ``unknown'' in the TYPE column when lsof can't obtain complete stat(2) results for the file. Usually the NAME column will contain a ``(stat: xxx)'' error message, but that could have been suppressed with the lsof ``-w'' option. 10.4 Linux ``mem'' Entry Problems 10.4.1 What do ``path dev=xxx'' and ``path inode=yyy'' mean in the NAME column of Linux ``mem'' file types? When the device or inode number in the process' ``maps'' file entry doesn't match the stat(2) results from the file path, lsof reports the inconsistent information from the stat(2) of the path parenthetically after the path in the NAME column in one of these forms: (path dev=xxx) only the device number, ``xxx'', from a stat(2) of the ``maps'' file entry path differs from the ``maps'' file entry value reported in the DEVICE column. (path inode=yyy) only the inode number, ``yyy'', from a stat(2) of the ``maps'' file entry path differs from the ``maps'' file entry value reported in the NODE column. (path dev=xxx inode=yyy) Both device and inode numbers differ. Lsof reports the ``maps'' file device number in the DEVICE column and the inode number in the NODE column. When device and inode mismatches occur, lsof suppresses the reporting of link count and size. See the answer to the "Why is neither link count nor size reported for some Linux ``DEL'' and ``mem'' file types?" question for more information. Device and inode inconsistencies can occur when a file at a ``maps'' path is replaced after the process has started, or when a different file system with similar path names is mounted on top of the original file system. The device inconsistency parenthetical messages can be suppressed with lsof's ``-w'' option. 10.4.2 Why is neither link count nor size reported for some Linux ``DEL'' and ``mem'' file types? Link count and size are not reported for some entries from the process' ``maps'' file because a stat(2) of the entry file path failed or stat(2) delivered device or inode numbers that don't match the ones in the ``maps'' entry. When the stat(2) device or inode numbers don't match those in the ``maps'' file entry, it is likely that the stat(2) results don't apply to the file that was originally mapped by the process and whose path appears in the ``maps'' file entry, so lsof tries to avoid reporting possibly incorrect information. See the answer to the "What do ``path dev=xxx'' and ``path inode=yyy'' mean in the NAME column of Linux ``mem'' file types?" for more information on how mismatched stat(2) device and inode numbers are reported. 10.5 Special Linux NAME column messages 10.5.1 What does ``(stat: xxx)'' mean in the NAME column of Linux files? When lsof tried to stat(2) the path in the NAME column, the stat(2) system call failed and produced an error message of ``xxx''. This situation usually occurs if the lsof process lacks permission to stat(2) the path -- e.g., the lsof executable lacks root permission, or lsof is attempting to stat(2) a path on an NFS device mounted with the root_squash option. The message can be suppressed with lsof's ``-w'' option. 10.5.2 What does ``(readlink: xxx)'' mean in the NAME column of Linux files? When lsof tried to convert the /proc/<PID>/fd path, reported in the NAME column, to its full and more meaningful path, the readlink(2) system call used to do the conversion failed. The readlink(2) failure message is ``xxx''. This situation usually occurs if the lsof process lacks permission to readlink(2) some part of the path -- e.g., the lsof executable lacks root permission, or lsof is attempting to stat(2) a path on an NFS device mounted with the root_squash option. The message can be suppressed with lsof's ``-w'' option. 10.6 Why is ``NOFD'' reported as a Linux file type? When lsof lacks permission to use opendir() on the fd/ subdirectory of a process' /proc/<PID> directory, it reports a single file of the type ``NOFD'' (for no file descriptors). Lsof reports the the /proc/<PID>/path in the NAME column, followed by "(opendir: xxx)", where ``xxx'' is the error message returned by opendir(). The ``NOFD'' entry can be suppressed with lsof's ``-w'' option. 10.7 Why does Linux lsof report a NAME column value that begins with ``/proc''? When lsof has problems processing a ``/proc/<PID>'' entry -- e.g., it can't convert the entry to a full and more meaningful path name, or it can't access the /proc/<PID>/fd subdirectory with opendir() -- it will report the /proc/<PID> path in the NAME column. 10.8 Linux /proc/net/tcp* and /proc/net/udp* issues 10.8.1 Why use the Linux -X option? If you're not interested in TCP/IP socket information for a particular use of lsof, adding the -X option will make lsof run more quickly, because -X inhibits the reading of the /proc/net/tcp* and /proc/net/udp* files. For example, you may only be interested in knowing what process has a particular file open. When the Linux system has a large number of open TCP/IP socket files, the time savings provided by -X can be significant. 10.8.2 Why does lsof say ``-i is useless when -X is specified''? If -X is specified, lsof can't report much information on open TCP/IP socket files. However, lsof's -i option requests that information. Hence, the two options conflict and can't be used together. 10.8.3 Why does lsof say ``can't identify protocol (-X specified)''? If the Linux lsof -X option is specified and an open socket file can't be identified without accessing the /proc/net/tcp* and /proc/net/udp* files, lsof will report that it can't identify the socket's protocol and that the failure may be caused by the -X specification 11.0 NetBSD Problems 11.1 Why doesn't lsof report on open kernfs files? Lsof doesn't report on open NetBSD kernfs files because the structures lsof needs aren't defined in the kernfs.h header file in /sys/misc/kernfs. 11.2 Why doesn't lsof report on open files on: file descriptor file systems; /proc file systems; 9660 (CD-ROM) file systems; MS-DOS (floppy disk) file systems; or kernel file systems? Lsof is not able to report on open files on certain file system if /usr/src/sys/msdosfs didn't exist when the lsof Configure script ran and lsof was made. /usr/src/sys/msdosfs contains header files lsof needs for collecting data on certain file system files. You can tell if an lsof executable above) lacks support for a file system if the following test of `lsof -v` produces nothing: $ lsof -v 2>&1 | grep <support_enabled_definition> The <support-enabled_definition> will be: File System Type Definition Note ---------------- ---------- ---- File descriptor HASFDESCFS /proc HASPROCFS 9660 HAS9660FS MS-DOS HASMSDOSFS (lsof 4.61 and above) Kernel HASKERNFS The work-around is to install /usr/src/sys, rerun the lsof Configure script, and remake lsof. 11.3 Why does lsof produce confusing results for nullfs file systems? Consider this report from /sbin/mount: /usr/home on /home type null (local) (According to /sbin/mount /usr/home is the mounted-on device and /home is the mounted-on directory.) When lsof is asked to report on open files on /home, it will report them as files on /usr/home instead. That's an artifact of the NetBSD kernel's dynamic name lookup cache (DNLC) and the way the kernel handles nullfs mounted-on directories. While lsof will report all open files on /home when given /home as a file system directory argument, even though reporting them as located on /usr/home, lsof will not find the same files when asked to report on all open files on /usr/home when given /usr/home as a file system device argument. That's because from the mount perspective /usr/home is equivalent to a device, but from the device perspective it is still a directory. So, what this lsof command reports: $ lsof /home ... NAME ... /usr/home/... Won't be duplicated by this lsof command: $ lsof /usr/home Another way to look at this confusing /home and /usr/home example is to consider what stat(2) reports. For /home stat(2) reports a device doublet that matches what lsof finds in open file node structures, while the device doublet stat(2) reports for /usr/home won't match what lsof finds. Nor does the mode reported by stat(2) indicate a block devices, as is the expected case. There is no simple answer to this confusion, nor is there even a simple explanation. Simply be aware that when supplying file system arguments to lsof on NetBSD, use the mounted-on directory name for a nullfs as the lsof argument, and don't be surprised when the NAME column reports the mounted-on device name. 11.4 NetBSD header file problems 11.4.1 Why can't the compiler find some NetBSD header files? If the compiler's pre-processor complains it can't find some header files when it compiles lsof source files, /usr/include and /usr/src may not have all the header files lsof needs. As a work-around use the NETBSD_SYS environment variable to specify to lsof the location of the additional header files -- e.g., % setenv NETBSD_SYS /my_source % ./Configure -n netbsd or $ NETBSD_SYS=/mys_source ./Configure -n netbsd Caution: using this work-around may cause the lsof Configure script to activate or omit different features, depending on where it finds the header files that determine the state of the features. 11.4.2 Why does NetBSD lsof produce incorrect output? If the NetBSD system's kernel was built from header files that don't match those in /usr/include -- e.g., //usr/src has the ones from which the kernel was built -- lsof may build, but won't produce correct output. As a possible work-around, try directing the C compiler to select header files from /usr/src before it selects them from /usr/include. That can be done with the DEBUG make string -- e.g., $ make DEBUG="-I/usr/src -I/usr/include" If that work-around fails, try using the LSOF_INCLUDE and NETBSD_SYS environment variables to swap /usr/include and /usr/src when running the Configure script, then use the make DEBUG string when running make -- e.g., $ LSOF_INCLUDE=/usr/src; export LSOF_INCLUDE $ NETBSD_SYS=/usr/include; export NETBSD_SYS $ ./Configure -n netbsd $ make DEBUG="-I/usr/src -I/usr/include" 11.5 Why isn't lsof feature xxx enabled for NetBSD? Lsof's Configure script enables NetBSD features by locating and examining header files associated with the features, and based on what it finds, setting compile-time definitions in Makefiles. (See 00PORTING for a list of the definitions.) When Configure doesn't find header files or doesn't find appropriate values in header files, that may mean the header file tree lsof is searching is incomplete or out of date. Lsof normally looks for NetBSD header files in /usr/include. It can also be directed to look in other directories -- e.g., /sys -- if told to do so with the contents of the LSOF_INCLUDE and NETBSD_SYS environment variables. To determine what header file enables a missing feature, check the NetBSD stanza in the Configure script. Then check the locations it checks for the indicated header files and contents. See 00XCONFIG for more information on LSOF_INCLUDE and and NETBSD_SYS. 12.0 NEXTSTEP and OPENSTEP Problems 12.1 Why can't lsof report on 3.1 lockf() or fcntl(F_SETLK) locks? Lsof has code to test for locks defined with lockf() or fcntl(F_SETLK) under NEXTSTEP 3.1, but that code has never been tested. I couldn't test it, because my NEXTSTEP 3.1 lockf() and fcntl(F_SETLK) functions return "Invalid argument" every way I have tried to invoke them. If your NEXTSTEP 3.1 system does allow you to use lockf() and fcntl(F_SETLK) and lsof doesn't report locks set with them, then the code in .../dialects/next/dnode.c probably isn't correct. Please contact me via e-mail at <abe@purdue.edu> and tell me how you got your lockf() and fcntl(F_SETLK) system calls to work. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 12.2 Why doesn't lsof compile for NEXTSTEP with AFS? I no longer have a NEXTSTEP test system that has AFS. Changes to lsof since I once had a test system have caused me to change the AFS code in NEXTSTEP without being able to test the changes. If you need AFS support for NEXTSTEP and can't get it to compile, please contact me. Perhaps we can jointly fix the problems. 13.0 OpenBSD Problems 13.1 Why doesn't lsof support kernfs on my OpenBSD system? Lsof supports the kernel file system on OpenBSD versions whose /sys/miscfs/kernfs/kernfs.h (or <miscfs/kernfs/kernfs.h> header file correctly defines the kern_target structure. The lsof Configure script's openbsd stanza checks for the presence of the structure's kt_name element and activates kernfs support for the CFLAGS -DHASKERNFS definition only when it finds kt_name. The kernfs.h header file is scheduled to be updated in the OpenBSD 2.1 release, according to Kenneth Stailey, who authored its changes. 13.2 Will lsof work on OpenBSD on non-x86-based architectures? I've not tested lsof on an OpenBSD system that uses a non-x86-based architecture, but I've had one report that lsof 4.33 compiles and works on OpenBSD for the pmax architecture (decstation 3100). 13.3 <sys/pipe.h> problems 13.3.1 Why does the compiler claim nbpg isn't defined? When compiling lsof on some (older) OpenBSD SPARC versions, the compiler may complain: In file included from ../dlsof.h:191, from ../lsof.h:166, from fino.c:52: /usr/include/sys/pipe.h:83: `nbpg' undeclared here (not in a function) /usr/include/sys/pipe.h:83: size of array `ms' has non-integer type This happens because <sys/pipe.h> uses NBPG from <machine/param.h> to size the `ms' array, and some OpenBSD systems define NBPG in terms of a kernel integer variable, nbpg. Lsof revisions 4.46 and above have a hack to dlsof.h, developed by Volker Borchert that avoids the compiler problem for SPARC OpenBSD 2.3. The hack might work for other OpenBSD SPARC versions, but hasn't been tested there. If you want to enable the hack for your OpenBSD SPARC version, modify this code in .../dialects/n+obsd/dlsof.h: # if defined(OPENBSDV) # if OPENBSDV==2030 && defined(__sparc__) # if defined(nbpg) #undef nbpg # endif /* defined(nbpg) */ #define nbpg 4096 /* WARNING!!! ... */ # endif /* OPENBSDV==2030 && defined(__sparc__) */ #include <sys/pipe.h> #endif /* defined(OPENBSDV) */ You will probably want to change the second #if test to match your OpenBSD version. You may also want to change what value is assigned to nbpg. See the next section, "What value should I assign to nbpg?" 13.3.2 What value should I assign to nbpg? If you need to enable the nbpg hack, described in "Why does the compiler claim nbpg isn't defined?", you may also need to assign a value other than 4096 to nbpg. 4096 works for the sun4c processor and should work for sun4m, but 8192 may be needed for sun4. Check <machine/param.h> and other OpenBSD documentation to determine the correct nbpg assignment. 13.4 Why doesn't lsof report on open MS-DOS file system (floppy disk) files? Lsof is not able to report on open MS-DOS file system files if /usr/src/sys/msdosfs didn't exist when the lsof Configure script ran and lsof was made. /usr/src/sys/msdosfs contains header files lsof needs for collecting data on MS-DOS file system files. You can tell if an lsof executable (revisions 4.61 and above) lacks MS-DOS file system support if the following command reports nothing: $ lsof -v 2>&1 | grep HASMSDOSFS The work-around is to install /usr/src/sys, rerun the lsof Configure script, and remake lsof. 13.5 Why isn't lsof feature xxx enabled for OpenBSD? Lsof's Configure script enables OpenBSD features by locating and examining header files associated with the features, and based on what if finds, setting compile-time definitions in Makefiles. (See 00PORTING for a list of the definitions.) When Configure doesn't find header files or doesn't find appropriate values in header files, that may mean the header file tree lsof is searching is incomplete or out of date. Lsof normally looks for OpenBSD header files in /usr/include and /sys. It can also be directed to look in other directories if told to do so with the contents of the LSOF_INCLUDE and NETBSD_SYS environment variables. To determine what header file enables a missing feature, check the OpenBSD stanza in the Configure script. Then check the locations it checks for the indicated header files and contents. See 00XCONFIG for more information on LSOF_INCLUDE and and NETBSD_SYS. 14.0 Output Problems 14.1 Why do the lsof column sizes change? Lsof dynamically sizes its output columns each time it runs to make sure that each column takes the minimum space. Column parsing -- e.g., with awk -- is possible, because each column is guaranteed to be separated from the preceding one by at lease one space, and no column except the last (NAME) contains embedded spaces. 14.2 Why does the offset have ``0t' and ``0x'' prefixes? The offset value that appears in the SIZE/OFF column has ``0t' and ``0x'' prefixes to distinguish it from size values that may appear in the same column. Normally if the offset value is less than 100,000,000 (8 digits), it appears in decimal with a ``0t' prefix; over 99,999,999, in hexadecimal with a ``0x'' prefix. A decimal offset is handy, for example, when tracking the progress of an outbound ftp transfer. When lsof reports on the ftp process, it will report the size of the file being sent with its open descriptor; it will report the progress of the transfer via the offset of the outbound open ftp data socket descriptor. The ``-o [n]'' option may be used to specify the maximum number of decimal digits to be printed after ``0t'' before lsof switches to the hexadecimal digits after `0x''. As already noted, the default decimal digit count is 8. 14.3 What are the values printed in the FILE_FLAG column and why is 0x<value> sometimes included? The two comma separated lists, separated by a semicolon, printed in the FILE-FLAG column (when the "+fg" option is specified), are short-hand names or hexadecimal values for the bits lsof finds in the f_flag or f_flags member of file structures for files (the first list, the one before the semicolon), and process open files flags found in various kernel structures, often named "pofile" (the second list, the one after the semicolon). Lsof determines the short-hand names from symbols in the <fcntl.h>, <linux/fs.h>, <sys/fcntl.h>, <sys/fcntlcom.h>, o<sys/file.h>, and <sys/user.h> header files. See the discussion of FILE-FLAG in the OUTPUT section of the lsof man page, and the FF_* and POF_* symbols in lsof.h for a list of the names. Bits with no names defined for them are represented by an 0x<value> member of the comma-separated list -- a hexadecimal integer. When "+fG" is specified (instead of "+fg"), lsof will list all flag values as two hexadecimal integers, separated by a semicolon. When "-FG" is specified to get the flags in an output field, the format defaults to hexadecimal. You can get names instead by following "-FG" with "+fg" -- e.g., $ lsof -FG +fg ... However, when you precede "-FG" with "+fg" -- e.g., $ lsof +fg -FG the format will be hexadecimal; order is important. 14.3.1 Why doesn't lsof display FILE_FLAG values for my dialect? All versions of lsof except the /proc-based Linux lsof report FILE-FLAG values. Lsof can't obtain FILE-FLAG information from the Linux /proc interface. 14.4 Network Addresses 14.4.1 Why does lsof's -n option cause IPv4 addresses, mapped to IPv6, to be displayed in IPv6 notation? When you use the -n option to tell lsof to display numeric network addresses, and an IPv4 address has been mapped to IPv6, lsof displays the address in IPv6 format and puts "ipv4" in the TYPE column. That combination indicates the IPv4 address has been mapped to IPv6. For example, the IPv4 address 1.2.3.4, when mapped to an IPv6 address, will be displayed by lsof as: [::ffff:1.2.3.4] The enclosing brackets are lsof's signal that this is an IPv6 address. Inside the brackets is a standard IPv6 address, reported by inet_ntop(). The first two colons, signifying zeroes in the first 64 bits of the IPv6 address, and the hexadecimal ffff in the next 32 bits, indicate that the last 32 bits contains a mapped IPv4 address, which is then displayed in IPv4 dot notation. 14.5 Why does lsof output \x, ^x, or \xnn for characters sometimes? Lsof displays only printable ASCII characters. Lsof considers a character printable if isprint(3) says it is. If isprint(3) says a character isn't printable, the lsof may page explains: "... Non-printable characters are printed in one of three forms: the C ``\[bfrnt]'' form; the control character `^' form (e.g., ``^@''); or hexadecimal leading ``\x'' form (e.g., ``\xab''). Space is non-printable in the COMMAND column (``\x20'') and printable elsewhere." 14.5.1 Why is space considered a non-printable character in command names? Space is considered an unprintable character in command names because it is sometimes possible to hide the full command name from scripts that parse ps(1) output by embedding a space in the name. 14.6 Why doesn't lsof print all the characters of a command name? By default lsof prints the first nine characters of the names of commands associated with processes. If more characters are required, the "w" value of the "+c w" option may be used to specify a larger width. If "w" is zero ('0') lsof will print all characters of all command names up to the limit of the number of characters supplied by the particular UNIX dialect. When reporting command names, lsof replaces non-printable characters as discussed in the answer to " Why does lsof output \x, ^x, or \xnn for characters sometimes?" See the answer to the "Why is space considered a non-printable character in command names?" question for an explanation of why spaces are replaced by the ``\x20'' representation in command names. The number of command name characters supplied to lsof by UNIX dialects in files and structures varies by dialect. For example, Linux 2.4.27 supplies lsof the first 15 characters of command names and Solaris 9 supplies 16. Thus, even if "w" is zero ('0'), lsof can't report more characters for command names on those two UNIX dialects than they provide lsof. 14.7 Why does lsof reject some -c command names, saying their lengths are "> what system provides (nn)"? The command name length that a specific system provides varies from dialect to dialect. As noted in the answer to the "Why doesn't lsof print all the characters of a command name?" question, Linux and Solaris provide a limited number of command name characters. When more characters are specified in the parameter to the -c option, lsof considers it an error and issues a fatal error message -- e.g., lsof: "-c xxxxyyyy" length (8) > what system provides (7) The only work-around is to specify no more characters to -c that the system provides to lsof. 14.8 Why does lsof sometimes print TYPE numbers instead of names? When lsof can't convert a type number to a name for printing in the TYPE column, it will report the number as four octets. 14.9 Marker line format problems 14.9.1 Why won't lsof accept a marker line format? Lsof's Configure script must find the localtime(3) and strftime(3) functions in the dialect's C library in order to enable support for marker line formats. Check the output of lsof's -v option for the presence of -DHAS_STRFTIME in the compiler flags. If it isn't there, Configure didn't find the necessary two C library functions. If you think lsof should have found the functions, make a copy of the C test program in the Configure script that it uses to find the functions. Then use the copy, or a more informative modification of it, to learn why Configure can't find the functions. You can find that program by searching for strftime. 14.9.2 Why does lsof reject the NL (%n) marker line format? When repeat mode and field output (with -F) have both been specified, lsof won't allow new line (NL) formats to be specified with ``%n''. That's because the marker line is always guaranteed to be a single line. There is no work-around to this restriction. 14.10 How are protocol state name exclusion and inclusion used? Protocol state name inclusion and exclusion with the ``-s p:s'' option and its arguments have some issues to consider. First, there is the problem of determining what state names, if any, the dialect produces. Try running this lsof command to find them: $ lsof -i Knowing the state names of interest, the next problem is to decide on the lsof options and their parameters that will produce the desired output. Here some examples are probably the most useful. To list only TCP socket files in LISTEN and CLOSE_WAIT states, use: $ lsof -itcp -stcp:listen,close_wait or $ lsof -iTCP -sTCP:LISTEN,CLOSE_WAIT Case isn't important to lsof in protocol and state names. To exclude TCP socket files in CLOSE_WAIT state, use: $ lsof -itcp -stcp:^close_wait Note the `^' preceding close_wait; it selects exclusion. You can mix included and excluded names in a comma separated list, but you may not include and exclude the same name for the same protocol. To list TCP files in LISTEN state and UDP files in Idle state, use: $ lsof -i -stcp:listen -sudp:idle Note: if you don't accompany the ``-s p:s'' list option and argguments with the -i option, lsof will list all other regular files, while applying the specified inclusion and exclusion specifications to network files. Generally, then, you want to use -i with -s. 14.10.1 Why doesn't my dialect support state name exclusion and inclusion? When state name inclusion and exclusion was added, I had access to test systems for AIX, Darwin, FreeBSD, Linux, PSTAT-based HP-UX and Solaris. Therefore, I was unable to add and test the support to any other UNIX dialects. If a dialect has the support, then the HASTCPUDPSTATE definition in its machine.h header file will be active; if not, it will be absent or commented out. If your dialect doesn't have the support and you want it added, you will have to provide me Internet access to a test host, where I can compile lsof and have the credentials to test the changes the support requires. If that's possible for you, please contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 15.0 Pyramid Version Problems 15.0.5 Statement of deprecation As of lsof revision 4.52 support for all Pyramid versions has been dropped. Contact me via e-mail at <abe@purdue.edu> if you are interested in obtaining the last lsof Pyramid distribution. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 16.0 SCO Problems 16.1 SCO OpenServer Problems 16.1.1 How can I avoid segmentation faults when compiling lsof? If you have an older SCO OpenServer compiler, it may get a segmentation fault when compiling some lsof modules. That appears to happen because of the -Ox optimization action requested in the lsof Makefile. Try changing -Ox to -O with this make invocation: $ make DEBUG=-O Bela Lubkin supplied this tip and Steve Williams verified it. 16.1.2 Where is libsocket.a? If you compile lsof and the loader says it can't find the socket library, libsocket.a, called by the -lsocket option in the lsof compile flags, you probably are running an SCO OpenServer release earlier than 5.0 and don't have the TCP/IP Development System package installed. You may have the necessary header files, because you have the TCP/IP run-time package installed, but if you don't have the TCP/IP Development System package installed, you won't have libsocket.a. Your choices are to install the TCP/IP Development System package or upgrade to OpenServer Release 5.0. You will find libsocket.a in 5.0 -- you'll find all the libraries and header files there, in fact -- and you can use gcc to compile lsof if you don't want to install the 5.0 Development System package. 16.1.3 Why do I get "warning C4200" messages when I compile lsof? When you compile lsof under OSR 3.2v4.2 (and perhaps under earlier versions as well), you may get many compiler warning messages of the form: node.c(183) : warning C4200: previous declarator is not compatible with default argument promotion In my opinion this is a bug in the OSR compiler. Because the compiler cannot handle full ANSI-C prototypes, it assumes default types for function parameters as it encounters untyped in a function prototype -- e.g., in this function declaration from node.c, readrnode(ra, r) KA_T ra; struct rnode *r; { ... the compiler assigns default int types to the ra and r arguments. Then, when the compiler encounters the fully typed parameters after the function skeleton and sees parameters with types that don't match the assumptions it previously made, it whines about its own assumptions. You can ignore these messages. 16.2 SCO|Caldera UnixWare Problems 16.2.1 Why doesn't lsof compile on my UnixWare 7.1.1 or above system? When you Configure lsof with the "uw" abbreviation and try to compile it for UnixWare 7.1.1, you may get compiler error messages like this: UX:acomp: ERROR: "dproc.c", line 98: undefined struct/union member: p_pgidp This suggest that you probably have a non-stop cluster UnixWare 7.1.1 system. Its <sys/proc.h> header file differs from the one on the system where I did the lsof port to UnixWare 7.1.1. I currently don't have access to a non-stop cluster system to be able to develop changes to lsof that would make it compile and work there. If you have a non-stop cluster UnixWare 7.1.1 system, want lsof for it, and can offer me a test account on the system, please contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. If you have a system with nsc_cfs and can offer me a test account on it, please contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 16.2.2 Why does lsof complain about node_self() on my UnixWare 7.1.1 or above system? If lsof exits immediately after issuing this message: can't identify process NSC node; node_self(): <message> It means that lsof has been built to run on a NonStop Cluster (NSC) UnixWare 7.1.1 or higher system and can't get the number of the node on which it is running. Lsof uses the node number to determine the path to the kernel boot file. You can tell if lsof has been built for NSC by looking for "-DHAS_UW_NSC" in lsof's "-v" option output. If the system on which you're trying to run lsof isn't running an NSC kernel, you will need to build a non-NSC lsof. 16.2.3 Why does UnixWare 7.1.1 or above complain about -lcluster, node_self(), or libcluster.so? When you build, compile, and load lsof for UnixWare 7.1.1 and above, ld may complain that it can't find the -lcluster library or that the node_self symbol is undefined. When you try to run an existing lsof binary it may complain that libcluster.so can't be found. These messages mean the tests made by Configure on your system led it to believe your system is running a NonStop Cluster (NSC) kernel, or the lsof binary you're trying to use was built on a NonStop Cluster system. If an lsof binary was built for NSC, this shell command produces output: $ strings <lsof_binary> | grep HAS_UW_NSC If that's not the case, and you can rebuild lsof, set the UW_HAS_NSC environment variable to "N" and do this: $ Configure -n clean $ UW_HAS_NSC=N $ export UW_HAS_NSC $ Configure -n uw $ make You can also edit Makefile and lib/Makefile. Remove -DHAS_UW_NSC from the CFGF strings. Remove -lcluster from the CFGL strings. Then run make again. If you have an existing NSC lsof binary and you want one for a non-NSC system, you will have to build lsof yourself on the system where you want to use it. (That's always a good idea anyway.) 16.2.4 Why does UnixWare 7.1.1 or above lsof complain it can't read the kernel name list? If lsof complains: can't read kernel name list from <path> It means that lsof can't find the booted kernel image file at <path>. On NonStop Cluster (NSC) UnixWare 7.1.1 or higher systems lsof determines the booted file path by examining this file: /stand/`node_self`/boot If examining that file doesn't lead to an NSC path, lsof uses: /stand/1/unix On non-NSC systems lsof expects the booted kernel image to be in /stand/unix. If your booted kernel image is in a different place, use lsof's "-k <path>" option to specify its path. 16.2.5 Why doesn't lsof report link count, node number, and size for some UnixWare 7.1.1 or above CFS files? Lsof reports link count, node number, and size for open CFS files as recorded in their kernel node structure's cached attributes. Sometimes not all attributes are cached on the node where lsof runs, so lsof cannot report them. 16.2.6 Why doesn't lsof report open files on all UnixWare 7.1.1 NonStop Cluster (NSC) nodes? Lsof can only report on files open on the node on which it runs, because the information lsof reports comes from the private kernel memory of the node. This may mean that asking lsof to find a specific open file, or use of a specific Internet address or port, may not report all open instances on nodes other than the one used to run lsof. You can use the NSC onnode(1) command to run lsof on specific nodes, or the onall(1) command to run lsof on all nodes -- e.g., $ onall lsof [options] 2>&1 | less or $ onnode node-number lsof [options] 2>&1 | less Note that, when lsof is run all nodes, the path name component assembly results it reports in its NAME column may vary, because the dynamic name cache from which lsof gets the components is private to the kernel of each node. Also note the use of shell redirection in the examples to merge the standard error file information from onnode and onall with lsof's standard output file output. That will put the onnode and onall node announcements in proper sequence with lsof's output. 16.2.7 Why doesn't lsof report the UnixWare 7.1.1 NonStop Cluster (NSC) node a process is using? To induce lsof to report the node on which a process runs would be a significant, non-standard modification to lsof. It has much wider implications than merely the printing of a number in an output column. I'm not currently (April 2001) prepared to undertake such a modification. If you want node-specific NSC information about open files, run lsof under the control of onall(1) or onnode(1). $ onall lsof [options] 2>&1 | less or $ onnode node-number lsof [options] 2>&1 | less 16.2.8 Why does the compiler complain about missing UnixWare 2.1[.x] header files? SCO|Caldera didn't ship the following header files with UnixWare 2.1 through 2.1.3: <fs/proc/prdata.h> <fs/procfs/prdata.h> <sys/fs/fifonode.h> <sys/fs/namenode.h> Lsof needs those header files for its compilation. Contact SCO|Caldera to get copies of those header files. If you can't get the header files from SCO|Caldera, please contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 17.0 Sun Problems 17.0.5 Statement of deprecation Lsof support for SunOS 4.1.x was last tested at revision 4.51. Contact me via e-mail at <abe@purdue.edu> if you're interested in obtaining it. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 17.1 My Sun gcc-compiled lsof doesn't work -- why? Gcc can be used to build lsof successfully. However, an improperly installed Sun gcc compiler will usually not produce a working lsof. If your Sun gcc-compiled lsof doesn't report anything, or reports ``can't read proc table,'' or gcc refuses to compile lsof without error, check that the gcc step that "fixes" Sun header files was run on the system where you're using gcc to compile lsof. As an alternative, if you have the SunPro C 5.0 compiler or later available, use it to compile lsof -- e.g., use the solariscc Configure abbreviations. 17.2 How can I make lsof compile with gcc under Solaris 2.[456], 2.5.1, 7, 8 or 9? Presuming your gcc-specific header files are wrong for Solaris, edit the lsof Configure-generated Makefile and lib/Makefile and make this change: CFGF= -Dsolaris=20400 ... to CFGF= -Dsolaris=20400 -D__STDC__=0 -I/usr/include ... or change: CFGF= -Dsolaris=20500 ... to CFGF= -Dsolaris=20500 -D__STDC__=0 -I/usr/include ... or change: CFGF= -Dsolaris=20501 ... to CFGF= -Dsolaris=20501 -D__STDC__=0 -I/usr/include ... This is only a temporary work-around. You really should instruct gcc to to update your gcc-specific header files or install a recent gcc (e.g., 3.2), which has no need for private copies of Solaris include files. 17.3 Why does Solaris Sun C complain about system header files? You're probably trying to use /usr/ucb/cc if you get compiler complaints like: cc -O -Dsun -Dsolaris=20300 ... "/usr/include/sys/machsig.h", line 81: macro BUS_OBJERR redefines previous macro at "/usr/ucbinclude/sys/signal.h", line 444 Note the reference to "/usr/ucbinclude/sys/signal.h". It reveals that the BSD Compatibility Package C compiler is in use. Lsof requires the ANSI C version of the Solaris C compiler, usually found in /usr/opt/bin/cc or /opt/SUNWspro/bin/cc. Try adding a CC string to the lsof Makefile that points to the Sun ANSI C version of the Sun C compiler -- e.g., CC= /usr/opt/bin/cc or CC= /opt/SUNWspro/bin/cc. 17.4 Why doesn't lsof work under my Solaris 2.4 system? If lsof doesn't work under your Solaris 2.4 system -- e.g., it produces no output, little output, or the output is missing command names or file descriptors -- you may have a pair of conflicting Sun patches installed. Solaris patch 101945-32 installs a kernel that was built with a <sys/auxv.h> header file whose NUM_*_VECTORS definitions don't match the ones in the <sys/auxv.h> updated by Solaris patch 102303-02. NUM_*_VECTORS in the kernel of patch 101945-32 are smaller than the ones in the <sys/auxv.h> of patch 102303-02. The consequence is that when lsof is compiled with the <sys/auxv.h> whose NUM_*_VECTORS definitions are larger than the ones used to compile the patched kernel, lsof's user structure does not align with the one that the kernel employs. If you have these two patches installed, contact Sun and complain about the mis-match. You may be able to work around the problem by editing /usr/include/sys/auxv.h to have the following NUM_*_VECTORS definitions: #define NUM_GEN_VECTORS 4 #define NUM_SUN_VECTORS 8 The Configure script issues a prominent WARNING that you should try the work-around. I thank Leif Hedstrom for identifying the offending patches. 17.5 Where are the Solaris header files? If you try to compile lsof under Solaris and get a compiler complaint that it can't find system header files, perhaps you forgot to add the header file package, SUNWhea. 17.6 Where is the Solaris /usr/src/uts/<architecture>/sys/machparam.h? When you try to Configure lsof for Solaris 2.[23456], 2.5.1, and 7 -- e.g., on a `uname -m` == sun4m system -- Configure complains: grep: /usr/src/uts/sun4m/sys/machparam.h: No such file or directory grep: /usr/src/uts/sun4m/sys/machparam.h: No such file or directory And when you try to compile the configured lsof, cc or gcc complains: dproc.c:530: `KERNELBASE' undeclared (first use this function) The explanation is that somehow your Solaris system doesn't have the header files in /usr/src/uts it should have. Perhaps someone removed the directory to save space. Perhaps you're using a gcc installation, copied from another system. In any event, you will have to load the header files from the SUNWhea package of your Solaris distribution. KERNELBASE is an important symbol to lsof -- it keeps lsof from sending an illegal kernel value to kvm_read() where a segmentation violation might result (a bug in the kvm library). Lsof can get illegal kernel values because it reads kernel values slowly with kvm_read() calls that the kernel is changing rapidly. Lsof doesn't need KERNELBASE at Solaris 2.5 and above, because it has a KERNELBASE value whose address lsof can find with /dev/ksyms and whose value it can read with kvm_read(). Under Solaris 2.5 /usr/src/uts has moved to /usr/platform. 17.7 Why does Solaris lsof say ``can't read proc table''? When lsof collects data on processes, using the kvm_*() functions to scan the kernel's proc structure table, it checks to make sure it has identified a reasonable number of them -- a minimum of three. When lsof can't identify three processes during a scan, it repeats the scan. When five scans fail to yield three processes, lsof issues the fatal message: lsof: can't read proc table and exits. Usually lsof fails to identify three processes during a scan because its idea of the form of the proc structure differs from that being used by the kernel. Since the proc structure is defined in <sys/proc.h> and other /usr/include header files, the root cause of a proc structure discrepancy usually can be found in the composition of /usr/include. One common way that /usr/include header files can be incorrect is that gcc was used to compile lsof, gcc used its special (i.e., "fixed") header files instead of the ones in /usr/include, and the special gcc header files weren't updated when Solaris was. Answers to these questions: My Sun gcc-compiled lsof doesn't work -- why? How can I make lsof compile with gcc under Solaris 2.[456], 2.5.1, 7, 8 or 9? Why does Solaris Sun C complain about system header files? discuss the gcc header file problem and offer suggestions on how to fix it or work around it. It may also be that you are trying to run a version of lsof that was compiled on an older version of Solaris. For example, an lsof executable, compiled for Solaris 2.4, will produce the ``can't read proc table'' message if you try to run it under Solaris 2.5. If you have compiled lsof under Solaris 2.5 and it still won't work, see if the header files in /usr/include have been updated to 2.5, or still represent a previous version of Solaris. Another source of header file discrepancies to consider is the Solaris patch level and whether a binary kernel patch was not matched with a corresponding header file update. See the "Why doesn't lsof work under my Solaris 2.4 system?" question for an example of one in Solaris 2.4 -- there may be other such patch conflicts I don't know about. 17.8 Why does Solaris lsof complain about a bad cached clone device? When lsof revisions below 4.04 have been run on a Solaris system and have been allowed to create a device cache file, the running of revisions 4.04 and above on the same systems may produce this complaint: lsof: bad cached clone device: ... lsof: WARNING: created device cache file: ... This is the result of a change in the device cache file that took place at lsof revision 4.04. The change introduced a node number into the clone device lines of the device cache file and was done in such a way that lsof could detect device cache files whose clone lines don't have node numbers (lines created by previous lsof revisions) and recognize the need to regenerate the device cache file. 17.9 Why doesn't Solaris make generate .o files? Solaris /usr/ccs/bin/make won't generate .o files from .c files if /usr/share/lib/make/make.rules is missing. It may be found in and installed from the SUNWsport package. 17.10 Why does lsof report some Solaris 2.3 and 2.4 lock types as `N'? For Solaris 2.3 with patch P101318 installed at level 45 or above, and for all versions of Solaris 2.4, NFS locks are represented by a NFS-specific kernel lock structure that sometimes lacks a read or write lock type indicator. When lsof encounters such a lock structure, it reports the lock type as `N'. 17.11 Why does lsof Configure say "WARNING: no cc in ..."? When lsof's Configure script is executed with the solariscc abbreviation it tries to make sure it's using the Sun C compiler and not the UCB substitute from /usr/ucb/cc. Thus, it looks for cc in the "standard" Sun compiler location, /opt/SUNWspro/bin. If Configure can't find cc there, it issues the warning: lsof: WARNING: no cc in /opt/SUNWspro/bin; using cc without path. and uses cc for the compiler name, letting the shell find cc with its PATH environment variable. You can tell Configure where to find your cc with the SOLARIS_CCDIR cross-configuration environment variable. (See 00XCONFIG for more information on SOLARIS_CCDIR). For example, use this Configure shell command: SOLARIS_CCDIR=/usr/special/bin Configure -n solariscc (SOLARIS_CCDIR should be the full path to the directory containing your cc.) 17.12 Solaris 7, 8 and 9 Problems 17.12.1 Why does lsof say the compiler isn't adequate for Solaris 7, 8 or 9? Solaris 7, 8 and 9 kernels come in two flavors, 32 and 64 bit. 64 bit kernels run on machines that support the SPARC v9 instruction set architecture. Separate executables for some programs, -- e.g., ones using libkvm like lsof -- must be built for 32 and 64 bit kernels. Previous Sun (e.g., SC4.0) and earlier gcc compilers will build lsof for 32 bit kernels, but they won't build it for 64 bit kernels. Compilers that will build lsof for 64 bit Solaris 7, 8 and 9 kernels are the Sun WorkShop Compilers C 5.0 and above, and recent gcc versions, e.g., 3.2. When given the ``-xarch=v9'' flag, the C 5.0 compiler and above, and associated loader and 64 bit libraries will build a 64 bit lsof executable; when given the "-m64" or "-mcpu=v9" (deprecated) flags, an appropriate gcc compiler will build a 64 bit lsof executable. When the lsof Configure script detects a 64 bit kernel is in use (e.g., by executing `/bin/isainfo -kv`), and when it finds that the specified compiler is inappropriate, it complains with these messages: For gcc: "!!!WARNING!!!=========!!!WARNING!!!=========!!!WARNING!!!" "! !" "! LSOF NEEDS TO BE CONFIGURED FOR A 64 BIT KERNEL, BUT !" "! THIS GCC DOESN'T SUPPORT THE BUILDING OF 64 BIT !" "! SOLARIS EXECUTABLES. LSOF WILL BE CONFIGURED FOR A !" "! 32 BIT echo KERNEL. !" "! !" "!!!WARNING!!!=========!!!WARNING!!!=========!!!WARNING!!!" For Sun C: !!!WARNING!!!==========!!!WARNING!!!==========!!!WARNING!!! ! ! ! LSOF NEEDS TO BE CONFIGURED FOR A 64 BIT KERNEL, BUT | ! THE VERSION OF SUN C AVAILABLE DOESN'T SUPPORT THE ! ! -xarch=v9 FLAG. LSOF WILL BE CONFIGURED FOR A 32 BIT ! ! KERNEL. ! ! ! !!!WARNING!!!==========!!!WARNING!!!==========!!!WARNING!!! 17.12.2 Why does Solaris 7, 8 or 9 lsof say "FATAL: lsof was compiled for..."? Solaris 7, 8 or 9 lsof may say: lsof: FATAL: lsof was compiled for a xx bit kernel, but this machine has booted a yy bit kernel. Where: xx = 32 or 64 yy = 64 or 32 (xx and yy won't match.) This message indicates that lsof was compiled for one size kernel and is being asked to execute on a different size one. That's not possible for programs like lsof that use libkvm. Depending on the instruction sets for which you need Solaris 7, 8 or 9 lsof, you may need two or more versions of lsof, compiled for each kernel size, installed for use with /usr/lib/isaexec. See the "How do I install lsof for Solaris 7, 8 or 9?" section of this document for more information on that. 17.12.3 How do I build lsof for a 64 bit Solaris kernel under a 32 bit Solaris kernel? If your Solaris system has an appropriate compiler (e.g., WorkShop Compilers C 5.0 and above, or a recent gcc like 3.2) and the 64 bit libraries have been installed, you can force lsof's Configure script to build a 64 bit version of lsof with: $ SOLARIS_KERNBITS=64 Configure -n solariscc The SOLARIS_KERNBITS environment variable is part of the lsof cross-configuration support, described in the 00XCONFIG file of the lsof distribution. 17.12.4 How do I install lsof for Solaris 7, 8 or 9? If you are installing lsof where it will be used only under the bit size kernel for which it was built, no special installation is required. If, however, you are installing different versions of lsof for different bit sizes -- e.g., for use on a 64 bit NFS server and from its 32 bit clients -- you should read the man page for isaexec(3C) and install lsof according to its instructions. The executable at the directory where lsof is to be found should be a hard link to /usr/lib/isaexec or a copy of it. In the directory there must be instruction architecture subdirectories -- e.g., .../sparc/ and .../sparcv9/. The lsof for 64 bit size kernels is installed in the .../sparcv9/ subdirectory; the one for 32 bit size kernels, in .../sparc/. For example, if you're installing 32 and 64 bit lsof executables in /usr/local/etc, you would: # cd /usr/local/etc # ln /usr/lib/isaexec lsof # mkdir sparc sparcv9 # install the 32 bit lsof as sparc/lsof # install the 64 bit lsof as sparcv9/lsof # chmod, chown, and chgrp sparc/lsof and sparcv9/lsof appropriately Lsof permissions and ownerships are the same whether one or more lsof executables are being installed, with or without the /usr/lib/isaexec hard link. 17.12.5 Why does my Solaris 7, 8 or 9 system say it cannot execute lsof? When you attempt to execute lsof, your Solaris 7, 8 or 9 shell may complain: ksh: ./lsof: cannot execute If the lsof executable exists and has the proper execution permissions, this error may be the result of trying to execute an lsof, built for a 64 bit kernel, on a 32 bit kernel. This will tell you about the lsof executable: $ file lsof lsof: ELF 64-bit MSB executable SPARCV9 Version 1, dynamically linked, not stripped The "64-bit" notation indicates the binary was built for a 64 bit kernel. To see the running kernel bit size, use this command: $ isainfo -kv 32-bit sparc kernel modules The "32-bit" notation indicates a 32 bit kernel has been booted. The only work-around is to obtain, or Configure and make, an lsof for the appropriate kernel bit size. If you Configure and make lsof on the kernel where you wish to run it the proper compiler, the lsof Configure step will generate Makefiles that can be used with make to build an appropriate lsof executable. To compile a 64 bit lsof, you must have an appropriate compiler -- i.e., Sun WorkShop Compilers C 5.0 or higher or a recent gcc like 3.2. 17.12.6 What gcc will produce 64 bit Solaris 7, 8 and 9 executables? 8 and 9 executables? Properly built and installed recent gcc versions -- e.g., 3.2 -- will build lsof for 64 bit Solaris kernels. If you update your gcc version to 3.2 or later, make sure the private gcc header files become current -- i.e., clear out any private header files from a previous gcc or Solaris installation before installing the new ones, or build to a new --prefix root and replace the old root with it after the build and installation are complete. 17.12.7 Why does lsof on my Solaris 7, 8 or 9 system say, "can't read namelist from /dev/ksyms?" You're probably trying to use an lsof executable built for an earlier Solaris release on a 64 bit Solaris 7, 8 or 9 kernel. The output from `lsof -v` will tell you the build environment of your lsof executable. You should also have gotten a warning message that lsof is compiled for a different Solaris version than the one under which it is running -- something like this: lsof: WARNING: compiled for Solaris release X; this is Y You need to build lsof on the system where you want to use it. For 64 bit Solaris 7, 8 and 9 you need a compiler that can generate 64 bit Solaris executables -- e.g., the Sun Workshop 5 C compiler or later, or a recent gcc version like 3.2. See the "Why does lsof say the compiler isn't adequate for Solaris 7, 8 or 9?" section and the ones following it for a discussion of building lsof for 64 bit Solaris 7, 8 or 9. 17.13 Solaris and COMMON 17.13.1 What does COMMON mean in the NAME column for a Solaris VCHR file? When lsof puts COMMON or (COMMON) in the NAME column of a Solaris VCHR file, it means that the file is handled by the special file system functions of the kernel through a common vnode. 17.13.2 Why does a COMMON Solaris VCHR file sometimes seem to have an incorrect minor device number? When lsof reports on an open file in a Solaris special file system that uses a COMMON vnode, and the file is a VCHR file, lsof tries to locate the associated device node by looking for matches on the major and minor device numbers first. If no major and minor match results, lsof then looks for a match on pseudo and clone device files. (See /devices/pseudo.) Those device nodes are matched specially by either their major or minor device numbers, but not both. Hence, when lsof finds a match under those special conditions, it may report a value in its output DEVICE column that differs from one of the major and minor numbers of the device node. Here's an example from a sun4m Solaris 7 system: $ ls -li /devices/pseudo/pm@0:pm 151261 crw-rw-rw- 1 root sys 117, 0 ... $ lsof /devices/pseudo/pm@0:pm COMMAND ... DEVICE ... NODE NAME powerd 117,1 ... 151261 /devices/pseudo/pm@0:pm (COMMON) Xsun ... 117,0 ... 151261 /devices/pseudo/pm@0:pm Note that the DEVICE value for the file with (COMMON) in its name field has a different minor device number (1) from what ls reports (0), while the DEVICE value for the file without (COMMON) matches the ls output exactly. Both match on the major device number, 117. The minor device number mis-match is a result of the way the Solaris kernel handles special file system common vnodes, and it's the reason lsof puts (COMMON) after the name to signal that a mis-match is possible. 17.14 Why don't lsof and Solaris pfiles reports always match? /usr/proc/bin/pfiles for Solaris 2.6, 7, 8, and 9 also reports information on open files for processes. Sometimes the information it reports differs from what lsof reports. There are several reasons why this might be true. First, because pfiles is a Sun product, based on Sun kernel features, its developers have a better chance of knowing exactly how open file information is organized. I sometimes have to guess at how kernel file structure linkages are constructed by gleaning hints from header files. Second, lsof is aimed at providing information, specifically device and node numbers, that can be used to identify named file system objects -- i.e., path names. Thus, lsof tries to make sure its device and node numbers match those reported by stat(2). Pfiles doesn't always report numbers that match stat(2) -- e.g., for files using clone and pseudo devices via common vnodes like the nlist() /dev/ksyms usage. Here's the Solaris 7 COMMON VCHR example again with additional pfiles output: $ ls -li /devices/pseudo/pm@0:pm 151261 crw-rw-rw- 1 root sys 117, 0 ... $ lsof /devices/pseudo/pm@0:pm vic1: 10 = lsof /dev/pm COMMAND ... DEVICE ... NODE NAME powerd ... 117,1 ... 151261 /devices/pseudo/pm@0:pm (COMMON) Xsun ... 117,0 ... 151261 /devices/pseudo/pm@0:pm $ pfiles ... 0: S_IFCHR ... dev:32,24 ino:61945 ... rdev:117,1 ... 14: S_IFCHR ... dev:32,24 ino:151261 ... rdev:117,0 Note that the NODE number, reported by lsof, matches what ls(1) and stat(2) report, while the ino value pfiles reports doesn't. Lsof also indicates with the (COMMON) notation that the DEVICE number is a pseudo one, derived from the character device's value. The lsof DEVICE value matches the pfiles rdev value, correct behavior for a character device, but pfiles gives no sign that it's not possible to find that character device number in /devices with ls(1) or stat(2). 17.15 Why does lsof say, "kvm_open(namelist=default, core=default): Permission denied?" Lsof needs permission to read from the /dev/kmem and /dev/mem memory devices. Access to them is opened via a call to the kvm_open() library function and it reports the indicated message. You must give lsof permission to read the memory devices. The super user can almost always do that, but other lsof users can do it if some group -- e.g., sys -- has permission to read the memory devices, and the lsof binary is installed with the group's ownership and with the setgid permission bit enabled. 17.16 Why is lsof slow on my busy Solaris UFS file system? Lsof may be slow on a busy Solaris UFS file system when UFS logging has been enabled with the "logging" mount option. That option can significantly increase disk operations under certain conditions -- e.g., when a lot of files are accessed quickly. When only the "logging" option is specified to mount, all file accesses (atime updates) are logged to the UFS logging queue. Each atime update requires two writes to the disk to complete it. If you want to do UFS logging -- and there are reliability advantages to it -- consider using the "logging,noatime" mount options instead. That will shift atime updates from the logging queue to fewer and independent asynchronous operations, consequently making the UFS logging queue a smaller bottleneck. Consult mount_ufs(1M) for more information on the logging and noatime options. (My thanks to Casper Dik for this tip on improving the performance of UFS logging.) 17.17 Why is lsof so slow on my Solaris 8 or 9 system? Solaris 8 has a post-release feature upgrade modifying kernel name cache (DNLC) handling that can slow lsof throughput dramatically. The feature, sometimes called negative DNLC caching, is standard in Solaris 9. As best I can tell, when you install the Solaris 8 MU1 package, you get negative DNLC caching. If this pipe produces any output, your system has negative DNLC caching. $ nm /dev/ksyms | grep negative_cache_vnode The reason negative DNLC caching perturbs lsof is that a single vnode address (found in the negative_cache_vnode kernel variable) is used to mark entries in the DNLC that are not (the negative part) found on disk. Since a single vnode address (the DNLC key lsof uses) can represent many (I've seen upwards of 30,000.) DNLC entries, their presence overloads lsof's internal DNLC hashing function. An overloaded hash function is a slow hash function, and lsof's slows to a crawl when it encounters thousands of keys that produce the same value when the lsof DNLC hash function is applied to them. The solution is simple -- ignore negative DNLC cache keys. They don't represent path name components lsof can use. Lsof revisions 4.50 and above have an addition that ignores them and the performance of those lsof revisions improves significantly when presented with negative DNLC cache keys. If you don't have an lsof revision at 4.51 or later, there's a work-around. Use lsof's ``-C'' option. It disables lsof's DNLC caching. Of course, that also inhibits the reporting of any path name components from the kernel DNLC. When ``-c'' is used, lsof will continue to report file system and character device paths. 17.18 Solaris and VxFS 17.18.1 Why doesn't lsof support VxFS 3.4 on Solaris 2.6, and above? Lsof will not support VxFS version 3.4 on Solaris 2.6 and above unless some files from VxFS Update 2 have been installed. VxFS 3.4 FCS and VxFS 3.4 update 1 lack the header files lsof normally uses to obtain information from the VxFS 3.4 kernel node structure, vx_inode. VxFS 3.4 Update 2 provides a method whereby lsof can obtain the necessary vx_inode information from the vxfsu_get_ioffsets() function in Veritas utility libraries. The utility libraries (32 bit and 64 bit versions) may be found in /opt/VRTSvxfs/lib. An ancillary header file may be found in /opt/VRTSvxfs/include/sys/fs/vx_libutil.h. Documentation of the vxfsu_get_ioffsets(3) function may be found in /opt/VRTS/man/man3/vxfsu_get_ioffsets.3. Those files of VxFS 3.4 Update 2 may be downloaded from: ftp://ftp.veritas.com/pub/support/vxfs_34.i64243.tar The vxfs_34.i64243.tar archive will unpack into an i64243 directory containing these files: $ ls i64243 README libvxfsutil.sol26.sums libvxfsutil.sol26.tar.Z libvxfsutil.sol27.sums libvxfsutil.sol27.tar.Z libvxfsutil.sol28.sums libvxfsutil.sol28.tar.Z Read README. Select the *.tar.Z file appropriate for your Solaris version. Its contents will unpack into /opt/VRTS and /opt/VRTSvxfs, so you will need sufficient permission -- e.g., do it as root -- to unpack the uncompressed archive. Once you've done that, it's a good idea to compare the checksums of the archive you unpacked with the ones recorded in the appropriate *.sums file. Use `sum -r` to verify the checksums. For example, if you want the Solaris 8 version, uncompress and unpack libvxfsutil.sol28.tar.Z -- e.g., $ su ... # cd i6423 # zcat libvxfsutil.sol28.tar.Z | tar xf - That should create these new files and subdirectories with the indicated checksums: File or subdirectory sum -r /opt/VRTSvxfs/include/vxfsutil.h 03938 /opt/VRTSvxfs/lib/libvxfsutil.a 51794 /opt/VRTSvxfs/lib/sparcv9/ /opt/VRTSvxfs/lib/sparcv9/libvxfsutil.a 07420 /opt/VRTS/man/man3/ /opt/VRTS/man/man3/vxfsu_get_ioffsets.3 62480 Once these files are in place, run lsof's Configure script for the solaris or solariscc abbreviation. Configure will locate the appropriate VxFS 3.4 Update 2 files and set up for the making of an lsof that will properly display open VxFS 3.4 file information. 17.18.2 Why does lsof report "vx_inode: vxfsu_get_ioffsets error" for open Solaris 2.6 and above VxFS 3.4 and above files? Even when lsof supports VxFS 3.4 and above on Solaris 2.6 and above, it may report "vx_inode: vxfsu_get_ioffsets error" in the NAME column for all VxFS files. The usual cause is that lsof doesn't have permission to read the file at the end of the /dev/vxportal symbolic link. If, for example, lsof has been installed setgid(sys), then the /dev/vxportal symbolic link destination should be owned by the sys group and readable by it. Update 2 for VxFS 3.4 sets the modes of the /dev/vxportal symbolic link destination to 0640 and the group ownership to sys. But I have had a report that the modes are wrong in a VxFS 4.0 installation. Another cause may be that the system has more than one version of VxFS installed (Only one can be active.), and lsof's Configure script did not choose the header files and libraries for the active VxFS version. Configure opts for VxFS 4.0 and above header files and libraries (in /opt/VRTS) in preference to those for VxFS below 4.0 (in /opt/VRTSvxfs). Look for the directories /opt/VRTS and /opt/VRTSvxfs. If you have /opt/VRTS, make sure its header and library symbolic links point to those of the active VxFS version. If you have both directories, look at the CFLAGS that Configure constructed for making lsof and see which directory path follows a -I option. If that doesn't match the directory path of the active VxFS version, try pointing Configure at the correct directory with the SOLARIS_VXFSINCL environment variable -- e.g., $ SOLARIS_VXFSINCL=/opt/.../include ./Configure -n solaris 17.18.3 Why does Solaris Configure claim there is no VxFS library? The lsof Configure script, when configuring for Solaris, may report: FATAL: no VxFS .../libvxfsutil.a That fatal error message indicates lsof has found the VxFS utility library's header files, but can't find the library itself in the expected location adjacent to the header files. One possible cause is an incorrect symbolic link from /opt/VRTS/lib/sparcv9/libvxfsutil.a to the library's real location. (Some VxFS distributions declared the link incorrectly.) Use `ls -lL` on that path to see if it exists. If it doesn't exist, the link may be missing an additional leading "../" component. If the problem is a missing "../" from the library's link, you can correct the link or check with Veritas/Symantec for the patch that corrects it. If the problem is not a missing "../", and you know the libvxfsutil.a location, you can define its path in the SOLARIS_VXFSLIB environment variable before running the lsof Configure script. (See 00XCONFIG for information about using the SOLARIS_VXFSLIB environment variable.) If you have no libvxfsutil.a, you must obtain it from Veritas/Symantec or find it in your VxFS installation package. 17.18.4 Why doesn't Solaris lsof report VxFS path name components? Solaris lsof will report path name components for VxFS versions that use the common Solaris Dynamic Name Lookup Cache (DNLC) or on some file systems of VxFS versions that support the VxFS Reverse Name Lookup (RNL) facility. VxFS versions 3.3 (approximately) and below use the common Solaris DNLC. (I haven't been able to determine exactly when VxFS stopped using the DNLC.) For versions above that boundary, but below 4.0, lsof can't report path name components. At VxFS 4.0 and above, lsof can be compiled to use the VxFS RNL facility for reporting path names. If "-DHASVXFSRNL" appears in the compiler flags section of lsof "-v" option output, then the lsof Configure script detected the VxFS RNL facility and lsof has been compiled to use it. Lsof's use of the RNL facility can fail when the VxFS file system disk layout version is below 6. In that case, lsof can report no path name components. For more information, see the vxfs_inotopath(3) manual page. any of the following commands will show the disk layout version for a VxFS file system, when supplied the block device or mount point on which the file system is mounted. fstyp -v <block_device> or mkfs -m <block_device> or vxupgrade <mount_point> You must have permission to read the block device -- e.g., be the root user. You may also be able to upgrade an older disk layout to one that will work with the RNL. See the vxupgrade(1M) man page for more information on that. When lsof can't report VxFS path name components, it reports the file system mount point and the path name of device on which it is mounted. The device path name is enclosed in parentheses. 17.18.5 Why does Solaris 10 lsof report scrambled VxFS paths? Solaris 10 lsof may report a bogus, scrambled path for an open VxFS file, when lsof obtains the path from a vnode's cached path. Veritas/Symantec reports that their Solaris 10 implementation has bugs in the way it handles the Solaris 10 vnode cached path and those bugs will be fixed in an upcoming patch some time after August 15, 2005. When Solaris 10 lsof reports a path for an open VxFs file obtained via the VxFS Reverse Name Lookup facility, the path will be correct. Also see the answers to the questions "Why does Solaris 10 lsof sometimes report the wrong path name?" and "Why doesn't Solaris lsof report VxFS path name components?" 17.19 Large file problems 17.19.1 Why does lsof complain it can't stat(2) a Solaris 2.5.1 large file? When given an argument that is the path to a Solaris 2.5.1 file, enable for large file operations with the O_LARGEFILE open(2) option, lsof complains that it can't stat(2) the file. That's because lsof isn't using a stat(2) call and associated structure enabled for large files. This error has been fixed, starting at lsof revision 4.58 for Solaris 2.6 and above. That fix won't work on Solaris 2.5.1 and I no longer have access to a Solaris 2.5.1 test system to develop a separate fix. The work-around is to avoid specifying a O_LARGEFILE path as an argument to lsof on Solaris 2.5.1. Instead use a combination of lsof and grep to achieve the same results, albeit more clumsily. 17.20 Why does lsof get a segmentation fault on 64 bit Solaris 8 using NIS+? I have received a report from Gary Craig that lsof produces a segmentation fault on his 64 bit Solaris 8 system using NIS+. Via an independent test program we have exonerated lsof and tracked the fault to the NIS+ __nis_server_name() function in the C name server library, -lnsl. Lsof causes the __nis_server_name() NIS+ function to be called by calling getservent() to read entries of the port number to service name map. The only Sun bug ID that appears to describe the problem is 4304244, although its text is unclear enough to leave room for doubt. Until Sun eliminates the __nis_server_name() segmentation fault cause, a work-around for lsof is to use its "-P" option, causing lsof to avoid port to service name lookups. 17.21 Will lsof crash the Solaris kernel? I've received and investigated one report that it has when the Sun hardware (a QME interface) was faulty. Today (May 23, 2002) I've learned that Sun has reports of kernel crashes caused by adb, lsof, and mdb. The Sun investigation pinpointed a problem in the /dev/kmem kernel driver and there is a Sun bug report, 4344513, about the problem. There is a fix in Solaris 9, and patches for Solaris 7 and 8 (SPARC and x86). To see if your Solaris system is fixed, look for a /devices/pseudo/*allkmem node. Extensive address filtering was added to lsof revision 4.50 to forestall what I then (July 2001) believed to be only the possibility that lsof might crash Solaris. However, the filtering isn't perfect, since a filtered address might become invalid after lsof has filtered it but before lsof has delivered it to /dev/kmem. That filtering work is described in .../dialects/sun/solaris_kaddr_filters, also available at: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/solaris_kaddr_filters The best and safest work-around is to upgrade to Solaris 9 or install an appropriate patch or its equivalent from this list: Solaris SPARC x86 Version Patch Patch ======= ===== ===== 7 106541-20 106542-20 8 108528-14 108529-14 17.22 Why does lsof on Solaris 7, 8, or 9 report a kvm_open() failure? When lsof is started on some Solaris 7, 8, and 9 systems it may report: lsof: kvm_open(namelist=default, corefile=default): \ No such file or directory Lsof revisions 4.65 and later will first report: lsof: cannot stat /dev/allkmem The second message, not delivered in lsof revisions below 4.65, explains the cause of the kvm_open() failure; it can't find /dev/allkmem. /dev/allkmem is a device added to Solaris 7 and 8 in patches and in the Solaris 9 FCS. See the preceding "Will lsof crash the Solaris kernel?" section for more information on /dev/allkmem and the patches. The kvm_open(3KVM) function in the KVM library of patched Solaris 7 and 8 systems and in Solaris 9 expects to find /dev/allkmem and exits on error when it does not. If you have installed the patch that updated your KVM library to a version that expects /dev/allkmem to be present and it is not, you may need to reconfigure your system's devices with devfsadm(1M) or enter "boot -r" to the OpenBoot monitor's prompt (usually "ok"). 17.23 Solaris and SAM-FS 17.23.1 Why does Solaris lsof report "(limited SAM-FS info)"? Lsof 4.68 and above report "(limited SAM-FS info)" on Solaris in the NAME column after the path or file system name for all files it finds on SAM-FS file systems. That's because no more information is known about the composition of the nodes that follow SAM-FS vnodes. If you can provide that information, please contact me via e-mail at <abe@purdue.edu>. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 17.23.2 Why can't lsof locate named SAM-GS files? Solaris lsof 4.68 and above can't locate files on SAM-FS file systems when the files are named as lsof arguments because lsof doesn't know how to locate open SAM-FS file device and node number information. (See also 'Why does Solaris lsof report "(limited SAM-FS info)?') 17.24 Lsof and Solaris 10 zones 17.24.1 How can I make lsof list the Solaris zone? Use the lsof "-z [z]" option. 17.24.2 Why doesn't lsof work in a Solaris 10 zone? When run from within a Solaris 10 zone, lsof will usually report: lsof: can't stat(/devices): No such file or directory That's because a Solaris zone usually has no /devices subdirectory, a restriction of the zone implementation intended to limit the ability of zone processes to control global system resources, including physical devices. While a zone may have a /dev subdirectory, that subdirectory usually lacks the /dev/allkmem, /dev/mem and /dev/kmem devices lsof and the KVM library it uses require. The work-around is to run lsof in the global zone. When it is run in a global zone lsof will be able to report on processes running in any zone, including the global zone. 17.24.3 Why does lsof complain it can't stat() Solaris 10 zone file systems? When run from the global zone on Solaris 10 lsof may complain: lsof: WARNING: can't stat() 15 zone file systems; using dev= options The warning message means lsof found the reported number of file system entries in the mount table for which it didn't have permission to get stat(2) results, but which had "zone=" and "dev=" mount table options. That is a normal restriction of Solaris 10 zones. Since the lsof warning message indicates it was able to find "dev=" options for the file systems, lsof will probably work correctly. One work-around is to relax the restrictions on zone mount points, so that lsof can stat() them. While that may be possible by changing directory modes or group ownerships, it is probably not a good idea, because it weakens the restrictions zones are intended to provide. Another work-around is to suppress the warning message with lsof's "-w" option. The down side of that is that it causes the suppression of all warning messages, leading to the possibility that some non-stat() warning messages will be suppressed. 17.25 Solaris 10 problems 17.25.1 Why does Solaris 10 lsof sometimes report the wrong path name? When a path name component is renamed -- e.g., with mv(1) -- Solaris 10 lsof may report the old component for an open file that used the component in its path before the rename. That's because Solaris 10 lsof reports the path name cached in the open file's vnode and the Solaris 10 kernel doesn't update the open vnode's cached path name when a component of it is changed. When an open file is deleted -- e.g., with rm(1) -- the path name by which it was opened remains cached in the vnode. Lsof can be instructed to display that path name with the -X option. The path name might be incorrect because of the rename problem described above. See the answer to the 'What does "(deleted)" mean in the NAME column of a Solaris 10 open file?' question for more information. Lsof is sometimes able to detect that cached path name is incorrect. In that case lsof may report only the mounted-on directory and device of the file system or it may report that the path name is of questionable accuracy by appending a trailing "(?)" to it in the NAME column. See the answer to the "Why does Solaris 10 lsof sometimes report only the mounted-on directory and device?" and 'What does "(?)" mean in the NAME column of a Solaris 10 open file?' questions for more information. 17.25.2 Why does Solaris 10 lsof sometimes report only the mounted-on directory and device? For some regular open files lsof may report only the mounted-on directory and device of the file system on which the file resides. That's because lsof was able to determine that the path name cached in the open file's vnode is incorrect. Lsof detects the cached path name is incorrect by applying stat(2) to it, provided that no error was detected when stat(2) was applied to the file system mounted-on directory during lsof setup. If a mounted-on directory stat(2) error was detected during setup, lsof does no cached path name analysis and simply reports it. When the application of stat(2) to the cached path name returns a no-entry reply (the ENOENT error number), lsof concludes the path no longer exists (i.e., has been unlinked) and reports the mounted-on directory and device of the file system. That behavior can be modified with the -X option in lsof revisions 4.77 and above. See the answer to the 'What does "(deleted)" mean in the NAME column of a Solaris 10 open file?' for more information. When the application of stat(2) to the cached path name returns a permission error reply (the EACCES or EPERM error numbers), lsof reports the cached path name and adds a trailing "(?)" to indicate the reported path name is of questionable accuracy. See the answer to the question 'What does "(?)" mean in the NAME column of a Solaris 10 open file?' for more information. If the application of stat(2) to the cached path name yields any other error reply, lsof reports the mounted-on directory and device of the file system. When the application of stat(2) to the cached path name succeeds, lsof compares the reported device and node numbers to what it has obtained for the open file from kernel structures. If they match, lsof reports the cached path name. If they don't match, lsof instead reports the mounted-on directory and device of the file system. A work-around that allows lsof to apply stat(2) successfully to cached path names is to give lsof sufficient permission to do it -- i.e., run lsof as the root user. 17.25.3 What does "(deleted)" mean in the NAME column of a Solaris 10 open file? When the -X option is specified to Solaris 10 lsof, it will report in its NAME column the path name cached for a deleted file in its vnode. The path name will be followed by "(deleted)". Note that the path name cached in a file's vnode is the path name by which the file was opened. It is not updated by the Solaris kernel when any path name component is changed. Hence, it may not represent the final path name the open file had. See the answer to the "Why does Solaris 10 lsof sometimes report the wrong path name?" question for more information on how changing a path name component affects the correctness of a what lsof reports. 17.25.4 What does "(?)" mean in the NAME column of a Solaris 10 open file? When lsof encounters a path name cached in the open file's vnode that stat(2) reports lsof lacks permission to access, lsof adds "(?)" to the path name reported in the NAME column to indicate the path name is of questionable accuracy. See the answers to the "Why does Solaris 10 lsof sometimes report the wrong path name?" and "Why does Solaris 10 lsof sometimes report only the mounted-on directory and device?" questions for more information on why lsof may report a path name of questionable accuracy. A work-around that allows lsof to apply stat(2) successfully to cached path names is to give lsof sufficient permission to do it -- i.e., run lsof as the root user. 17.26 Solaris contract file problems 17.26.1 Why doesn't lsof report size, link count and node number for Solaris 10 contract files? Lsof doesn't report size, link count or node number for Solaris 10 contract files because I don't know how to obtain them from contract file kernel structures. 17.26.2 Why can't lsof locate a Solaris 10 contract file by path name? Because lsof can't find the node number of Solaris contract files, it can't match the device and node numbers it gets from applying stat(2) to the contract file path name with what it finds in kernel data. 17.27 Solaris 10 ZFS probblems 17.27.1 Why does Configure ask for the location of ZFS header files? To provide ZFS support when lsof is compiled it needs to have access to the definitions of ZFS structures used by the kernel. Those definitions are contained in header files that Sun does not distribute with Solaris 10. When the Configure script detects the system might support ZFS by finding the <sys/fs/zfs.h> header file, it checks for the required ZFS kernel structure definition header files. When they are not found, it asks if ZFS support should be included and if so, with what definitions. Two sources can be declared for definitions: 1) lsof's internal ones; or 2) the necessary header files at some location other than /usr/include/sys. The necessary header files are: dmu.h zfs_acl.h zfs_debug.h zfs_rlock.h zil.h spa.h zfs_context.h zfs_dir.h zfs_vfsops.h zio.h txg.h zfs_ctldir.h zfs_ioctl.h zfs_znode.h zio_impl.h The necessary header files might have been obtained, for example, from the http://src.opensolaris.org Open Solaris source site. However, the Open Solaris header files might not be adequate -- see the answer to the "Why don't the Open Solaris ZFS header files provide correct ZFS kernel structure definitions?' question for information on why the Open Solaris ZFS header files might not provide correct ZFS kernel structure definitions. The supplied header file path must point to a directory that contains a sys/ subdirectory where the matching header files are located -- e.g., if the supplied path is /tmp/zfs, then /tmp/zfs/sys must contain the necessary header files. See the answer to the "Why do -h and -v output warn about possibly inaccurate ZFS kernel structure definitions?" question for information on the risks associated with using lsof's internal definitions. 17.27.2 Why do -h and -v output warn about possibly inaccurate ZFS kernel structure definitions? When lsof is configured to use its internal ZFS kernel structure definitions, there is the chance that the definitions may be out of date. Hence, an lsof built with them may report incorrect device numbers, file sizes, node numbers and link counts. Please contact me via e-mail at <abe@purdue.edu> for work-around suggestions. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 17.27.3 Why don't the Open Solaris ZFS header files provide correct ZFS kernel structure definitions? The Open Solaris ZFS header files may not provide correct ZFS kernel definitions. An lsof built with them may report incorrect device numbers, file sizes, node numbers and link counts. The definitions may be incorrect because the Open Solaris header files are not synchronized with any particular Solaris 10 release. Consequently they might contain modifications to the structures not in the structure definitions used to build the running kernel. It may be that only Sun has header files that match the kernel structures of the running Solaris 10 kernel. Please contact me via e-mail at <abe@purdue.edu> for work-around suggestions. Make sure "lsof" appears in the "Subject:" line so my e-mail filter won't classify your letter as Spam. 18.0 Lsof Features 18.1 Why doesn't lsof doesn't report on /proc entries on my system? /proc file system support is generally available only for BSD, SYSV R4 dialects, and Tru64 UNIX (Digital UNIX, DEC OSF/1). It's also available for Linux, and Pyramid DC/OSx and Reliant UNIX. Even on some SYSV R4 dialects I encountered many problems while trying to incorporate /proc file system support. The chief problem is that some vendors don't distribute the header file that describes the /proc file system node -- usually called prdata.h. 18.2 How do I disable the device cache file feature or alter it's behavior? To disable the device cache file feature for a dialect, remove the HASDCACHE definition from the machine.h file of the dialect's machine.h header file. You can also use HASDCACHE to change the default prefix (``.lsof'') of the device cache file. Be sure you consider disabling the device cache file feature carefully. Having a device cache file significantly reduces lsof startup overhead by eliminating a full scan of /dev (or /devices) once the device cache file has been created. That full scan also overloads the kernel's name cache with the names of the /dev (or /devices) nodes, reducing the opportunity for lsof to find path name components of open files. If you're worried about the presence of mode 0600 device cache files in the home directories of the real user IDs that execute lsof, consider these checks that lsof makes on the file before using it: 1. To read the device cache file, lsof must gain permission from access(2). 2. The device cache file's modes must be 0600 (0644 if lsof is reading a system-wide device cache file) and its size non-zero. 3. There must be a correctly formatted section count line at the beginning of the file. 4. Each section must have a header line with a count that properly numbers the lines in the section. Legal sections are device, clone, pseudo-device, and CRC. 5. The lines of a section must have the proper format. 6. All lines are included in a 16 bit CRC, and it is recorded in a non-checksummed section line at the end of the file. 7. The checksum computed when the file is read must match the checksum recorded when the file was written. 8. The checksum section line must be followed by end-of-information. 9. Lsof must be able to get matching results from stat(2) on a randomly chosen entry of the device section. For more information on the device cache file, read the 00DCACHE file of the lsof distribution. 18.2.1 What's the risk with a perverted device cache file? Even with the checks that lsof makes on the device cache file, it's conceivable that an intruder could modify it so it would pass lsof's tests. The only serious consequence I know of this change is the removal of a file whose major device number identifies a socket from some user ID's device cache file. When such a device has been removed from the device cache file, and when lsof doesn't detect the removal, lsof may not be able to identify socket files when executed by the affected user ID. Only certain dialects are at risk to this attack -- e.g., SCO OpenServer and Solaris 2.x, 7, 8, and 9. If you're tracking a network intruder with lsof, that could be important to you. If you suspect that someone has corrupted the device cache file you're using, I recommend you use lsof's -Di option to tell it to ignore it and use the contents of /dev (or /devices) instead; or remove the device cache file (usually .lsof_hostname, where hostname is the first component of the host's name returned by gethostname(2)) from the user ID's home directory and let lsof create a new one for you. 18.2.2 How do I put the full host name in a personal device cache file path? Lsof constructs the personal device cache file path name from a format specified in the HASPERSDC #define in the dialect's machine.h header file. As distributed HASPERSDC declares the path to be ``.lsof_'' plus the first component of the host name with the format ``.lsof_%L''. If you want to change the way lsof constructs the personal device cache file path name, you can change the HASPERSDC #define and recompile lsof. If, for example, you #define HASPERSDC to be ``.lsof_%l'' (note the lower case `l'), Configure and remake lsof, then the personal device cache file path will be ``.lsof_'' plus the host name returned by gethostname(2). See the 00DCACHE file of the lsof distribution for more information on the formation of the personal device cache file path and the use of the HASPERSDC #define. 18.2.3 How do I put the personal device cache file in /tmp? Change the HASPERSDC definition in your dialect's machine.h header file. When you redefine HASPERSDC, make sure you put at least one user identification conversion in it to keep separate the device cache files for each user of lsof. Also give some thought to including the ``%0'' conversion to define an alternate path for setuid-root and root processes. Here's a definition that puts a personal device cache file in /tmp with the name ``.lsof_login_hostname_pers''. #define HASPERSDC "/tmp/.lsof_%u_%l_pers" Thus the /tmp personal device cache file path for login "abe" on host "lsof.itap.purdue.edu" would be: /tmp/.lsof_abe_lsof.itap.purdue.edu_pers You can add the User ID (UID) with the "%U" conversion and the first host name component with the ``%L'' conversion. CAUTION: be careful using absolute paths like /tmp lest lsof processes that are setuid-root or whose real UID is root be used to exploit some security weakness via /tmp. Elect instead to add an alternate path for those processes with the ``%0'' conversion. Here's an extension of the previous HASPERSDC format for /tmp that declares an alternate path: #define HASPERSDC "/tmp/.lsof_%u_%l_pers%0%h/.lsof_%L" When the lsof process is setuid-root or its real UID is root, presuming root's home directory is `/' and the host's name is ``lsof.itap.purdue.edu'', the extended format yields: /.lsof_vic 18.3 Why doesn't lsof know about AFS files on my favorite dialect? Lsof currently supports AFS for these dialects: AIX 4.1.4 (AFS 3.4a) Linux 1.2.13 (AFS 3.3) NEXTSTEP 3.2 (AFS 3.3) Solaris 2.[56] (AFS 3.4a) It may recognize AFS files on other versions of these dialects, but I have no way to test that. Lsof may report correct information for AFS files on other dialects, but I can't test that either. AFS support must be custom crafted for each UNIX dialect and then tested. If lsof supports your favorite dialect, but doesn't recognize its AFS files, probably I don't have access to a test system. If you want AFS support badly for your dialect, consider helping me do the development and testing. 18.3.1 Why doesn't lsof report node numbers for all AFS volume files, or how do I reveal dynamic module addresses to lsof? When AFS is implemented via dynamic kernel modules -- e.g., in NEXTSTEP -- lsof can't obtain the addresses of AFS variables in the kernel that it uses to identify AFS vnodes. It can guess that a vnode is assigned to an AFS file and it can obtain other information about AFS files, but it has trouble computing AFS volume node numbers. To determine node numbers for AFS volumes other than the root volume, /afs, lsof needs access to a hashed volume structure pointer table. When it can't find the address of that table, because AFS support is implemented via dynamic kernel modules, lsof will return blanks in the INODE column for AFS volume files. Lsof can identify the root volume's node number (0), and can compute the node numbers for all other AFS files. If you have a name list file that contains the addresses of the AFS dynamic modules -- e.g., you saved module symbols when you created a loadable module kernel with modload(8) by specifying -sym -- lsof may be able to find the kernel addresses it needs in that file. Lsof looks up AFS dynamic kernel addresses for these dialects at these default paths: NEXTSTEP 3.2 /usr/vice/etc/afs_loadable A different path to a name list file with AFS dynamic kernel addresses may be specified with the -A option, when the -A option description appears in lsof's -h or -? (help) output. If any addresses appear in the -A name list file that also appear in the regular kernel name list file -- e.g., /vmunix -- they must match, or lsof will silently ignore the -A addresses on the presumption that they are out of date.
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