Edit File: commands.txt
:mod:`commands` --- Utilities for running commands ================================================== .. module:: commands :platform: Unix :synopsis: Utility functions for running external commands. .. sectionauthor:: Sue Williams <sbw@provis.com> The :mod:`commands` module contains wrapper functions for :func:`os.popen` which take a system command as a string and return any output generated by the command and, optionally, the exit status. The :mod:`subprocess` module provides more powerful facilities for spawning new processes and retrieving their results. Using the :mod:`subprocess` module is preferable to using the :mod:`commands` module. .. note:: In Python 3.x, :func:`getstatus` and two undocumented functions (:func:`mk2arg` and :func:`mkarg`) have been removed. Also, :func:`getstatusoutput` and :func:`getoutput` have been moved to the :mod:`subprocess` module. The :mod:`commands` module defines the following functions: .. function:: getstatusoutput(cmd) Execute the string *cmd* in a shell with :func:`os.popen` and return a 2-tuple ``(status, output)``. *cmd* is actually run as ``{ cmd ; } 2>&1``, so that the returned output will contain output or error messages. A trailing newline is stripped from the output. The exit status for the command can be interpreted according to the rules for the C function :cfunc:`wait`. .. function:: getoutput(cmd) Like :func:`getstatusoutput`, except the exit status is ignored and the return value is a string containing the command's output. .. function:: getstatus(file) Return the output of ``ls -ld file`` as a string. This function uses the :func:`getoutput` function, and properly escapes backslashes and dollar signs in the argument. .. deprecated:: 2.6 This function is nonobvious and useless. The name is also misleading in the presence of :func:`getstatusoutput`. Example:: >>> import commands >>> commands.getstatusoutput('ls /bin/ls') (0, '/bin/ls') >>> commands.getstatusoutput('cat /bin/junk') (256, 'cat: /bin/junk: No such file or directory') >>> commands.getstatusoutput('/bin/junk') (256, 'sh: /bin/junk: not found') >>> commands.getoutput('ls /bin/ls') '/bin/ls' >>> commands.getstatus('/bin/ls') '-rwxr-xr-x 1 root 13352 Oct 14 1994 /bin/ls' .. seealso:: Module :mod:`subprocess` Module for spawning and managing subprocesses.
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