Software: Apache/2.0.54 (Fedora). PHP/5.0.4 

uname -a: Linux mina-info.me 2.6.17-1.2142_FC4smp #1 SMP Tue Jul 11 22:57:02 EDT 2006 i686 

uid=48(apache) gid=48(apache) groups=48(apache)
context=system_u:system_r:httpd_sys_script_t 

Safe-mode: OFF (not secure)

/usr/share/doc/db4-devel-4.3.27/ref/log/   drwxr-xr-x
Free 3.57 GB of 27.03 GB (13.2%)
                            Encoder    Tools    Proc.    FTP brute    Sec.    SQL    PHP-code    Update    Feedback    Self remove    Logout    

Viewing file:     intro.html (6.07 KB)      -rw-r--r--

Berkeley DB Reference Guide: Logging Subsystem

Berkeley DB and logging

The Logging subsystem is the logging facility used by Berkeley DB. It is largely Berkeley DB-specific, although it is potentially useful outside of the Berkeley DB package for applications wanting write-ahead logging support. Applications wanting to use the log for purposes other than logging file modifications based on a set of open file descriptors will almost certainly need to make source code modifications to the Berkeley DB code base.

A log can be shared by any number of threads of control. The DB_ENV->open method is used to open a log. When the log is no longer in use, it should be closed using the DB_ENV->close method.

Individual log entries are identified by log sequence numbers. Log sequence numbers are stored in an opaque object, a DB_LSN.

The DB_ENV->log_cursor method is used to allocate a log cursor. Log cursors have two methods: DB_LOGC->get method to retrieve log records from the log, and DB_LOGC->close method to destroy the cursor.

There are additional methods for integrating the log subsystem with a transaction processing system:

DB_ENV->log_flush

Flushes the log up to a particular log sequence number.

log_compare

Allows applications to compare any two log sequence numbers.

DB_ENV->log_file

Maps a log sequence number to the specific log file that contains it.

DB_ENV->log_archive

Returns various sets of log filenames. These methods are used for database administration; for example, to determine if log files may safely be removed from the system.

DB_ENV->log_stat

The display db_stat utility uses the DB_ENV->log_stat method to display statistics about the log.

DB_ENV->remove

The log meta-information (but not the log files themselves) may be removed using the DB_ENV->remove method.

Copyright (c) 1996-2004 Sleepycat Software, Inc. - All rights reserved.