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<title>Berkeley DB: DB_ENV-&gt;set_mp_max_openfd</title>
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DB_ENV-&gt;set_mp_max_openfd
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#include &lt;db.h&gt;

int
DB_ENV-&gt;set_mp_max_openfd(DB_ENV *env, int maxopenfd);

int
DB_ENV-&gt;get_mp_max_openfd(DB_ENV *env, int *maxopenfdp);
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Description: DB_ENV-&gt;set_mp_max_openfd
The DB_ENV-&gt;set_mp_max_openfd method limits the number of file descriptors
the library will open concurrently when flushing dirty pages from the
cache.
The database environment's limit on open file descriptors to flush dirty pages may also be configured using the
environment's <a href="../../db4-devel-4.7.25/ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file. The syntax of the entry in that
file is a single line with the string "set_max_openfd", one or more whitespace
characters, and the number of open file descriptors.
Because the <a href="../../db4-devel-4.7.25/ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file is read when the database environment
is opened, it will silently overrule configuration done before that
time.
The <a href="../../db4-devel-4.7.25/api_c/memp_maxwrite.html">DB_ENV-&gt;set_mp_max_write</a> method configures a database environment, not only operations
performed using the specified <a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a> handle.
The DB_ENV-&gt;set_mp_max_openfd method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 maxopenfd<ul compact><li>The maximum number of file descriptors that may be concurrently opened
by the library when flushing dirty pages from the cache.</ul>
 
 Errors
The DB_ENV-&gt;set_mp_max_openfd method
may fail and return one of the following non-zero errors:
 
EINVAL<ul compact><li>An
invalid flag value or parameter was specified.</ul>
 
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Description: DB_ENV-&gt;get_mp_max_openfd
The DB_ENV-&gt;get_mp_max_openfd method returns the maximum number of file descriptors open.
The DB_ENV-&gt;get_mp_max_openfd method may be called at any time during the life of the
application.
The DB_ENV-&gt;get_mp_max_openfd method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 maxopenfdp<ul compact><li>The DB_ENV-&gt;get_mp_max_openfd method returns the
maximum number of file descriptors open in maxopenfdp.</ul>
 
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 Class
<a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a>, <a href="../../db4-devel-4.7.25/api_c/mempfile_class.html">DB_MPOOLFILE</a>
 See Also
<a href="../../db4-devel-4.7.25/api_c/memp_list.html">Memory Pools and Related Methods</a>
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