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<! "@(#)file.so 10.10 (Sleepycat) 10/4/98">
<!Copyright 1997, 1998 by Sleepycat Software, Inc. All rights reserved.>
<html>
<body bgcolor=white>
<head>
<title>Berkeley DB: log_file</title>
<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit.">
<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btr
ee,hash,hashing,transaction,transactions,locking,logging,access method,access me
thods,java,C,C++">
</head>
<h1>log_file</h1>
<hr size=1 noshade>
<tt>
<h3>
<pre>
#include <db.h>
<p>
int
log_file(DB_LOG *logp,
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 the value of <b>errno</b> on failure, and 0 on success.
<p>
<h1>Errors</h1>
If a fatal error occurs in Berkeley DB, the log_file function may fail and return
DB_RUNRECOVERY, at which point all subsequent database calls will also
return DB_RUNRECOVERY.
<p>
The log_file
function may fail and return <b>errno</b>
for any of the errors specified for the following Berkeley DB and C library
functions:
abort(3),
close(3),
fcntl(3),
fflush(3),
fprintf(3),
free(3),
getenv(3),
getpid(3),
getuid(3),
isdigit(3),
malloc(3),
memcpy(3),
memset(3),
open(3),
sigfillset(3),
sigprocmask(3),
snprintf(3),
stat(3),
strcpy(3),
strerror(3),
strlen(3),
unlink(3),
vfprintf(3),
and
vsnprintf(3).
<p>
In addition, the log_file
function may fail and return <b>errno</b>
for the following conditions:
<dl compact>
<p><dt>ENOMEM<dd>The supplied buffer was too small to hold the log file name.
</dl>
<p>
<h1>See Also</h1>
<a href="../../api_c/DbLog/archive.html">log_archive</a>,
<a href="../../api_c/DbLog/close.html">log_close</a>,
<a href="../../api_c/DbLog/compare.html">log_compare</a>,
log_file,
<a href="../../api_c/DbLog/flush.html">log_flush</a>,
<a href="../../api_c/DbLog/get.html">log_get</a>,
<a href="../../api_c/DbLog/open.html">log_open</a>,
<a href="../../api_c/DbLog/put.html">log_put</a>,
<a href="../../api_c/DbLog/db_register.html">log_register</a>,
<a href="../../api_c/DbLog/stat.html">log_stat</a>,
<a href="../../api_c/DbLog/unlink.html">log_unlink</a>
and
<a href="../../api_c/DbLog/db_unregister.html">log_unregister</a>.
</tt>
</body>
</html>
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