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<h1>log_file</h1>
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<h3><pre>
#include &lt;db.h&gt;
<p>
int
log_file(DB_ENV *env,
    const DB_LSN *lsn, char *namep, size_t len);
</pre></h3>
<h1>Description</h1>
<p>The log_file function maps
DB_LSN structures
to file names,
copying the name of the file containing the record named by <b>lsn</b>
into the memory location referenced by <b>namep</b>.
<p>The <b>len</b> argument is the length of the <b>namep</b> buffer in bytes.
If <b>namep</b> is too short to hold the file name, log_file will
return ENOMEM.
(Log file names are normally quite short, on the order of 10 characters.)
<p>This mapping of
DB_LSN structures
to files is needed for database administration.  For example, a
transaction manager typically records the earliest
DB_LSN
needed for restart, and the database administrator may want to archive
log files to tape when they contain only
DB_LSN
entries before the earliest one needed for restart.
<p>The log_file function returns a non-zero error value on failure and 0 on success.
<h1>Errors</h1>
<p>The log_file function may fail and return a non-zero error for the following conditions:
<p><dl compact>
<p><dt>ENOMEM<dd>The supplied buffer was too small to hold the log file name.
</dl>
<p>The log_file function may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions.
If a catastrophic error has occurred, the log_file function may fail and return
<a href="../ref/program/errorret.html#DB_RUNRECOVERY">DB_RUNRECOVERY</a>, in which case all subsequent Berkeley DB calls will fail
in the same way.
<h1>See Also</h1>
<a href="../api_c/env_set_lg_bsize.html">DBENV-&gt;set_lg_bsize</a>,
<a href="../api_c/env_set_lg_max.html">DBENV-&gt;set_lg_max</a>,
<a href="../api_c/log_archive.html">log_archive</a>,
<a href="../api_c/log_compare.html">log_compare</a>,
<a href="../api_c/log_file.html">log_file</a>,
<a href="../api_c/log_flush.html">log_flush</a>,
<a href="../api_c/log_get.html">log_get</a>,
<a href="../api_c/log_put.html">log_put</a>,
<a href="../api_c/log_register.html">log_register</a>,
<a href="../api_c/log_stat.html">log_stat</a>
and
<a href="../api_c/log_unregister.html">log_unregister</a>.
</tt>
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