Revision history for Perl extension BDB::Wrapper.

0.51 Sun Mar/02/2020
	- added necessary modules and description of cds_lock

0.50 Sun Aug/16/2013
  - By specifying no_lock for new DBB::Wrapper object, you can use transaction without lock, which can be used when you need only read dbh.

0.49 Sun Mar/28/2013
  - added txn=>1 and transaction=>1 options to use /tmp/txn_data directory for transaction's home directory

0.48 Tue Jan/22/2013 3:00
	- Modification of the document for cds_lock

0.47 Sun Jan/20/2013 13:57
	- Modification for transaction

0.46 Mon Oct 08 12:50:00
	- Modified document for pod

0.45 Mon Oct 08 01:00:00
	- Bug fix for SIG{ALRM}

0.44
	- Just modifiction of document not related to functions

0.43
	- Skipped for bug

0.42 Wed Jan 12 06:50:00
	- Improved how to use wait limitation

0.41 Tue Jan 11 01:50:00
	- Added error explanation

0.40 Sun Jan 09 21:52:00
	- Adjust option of create_read_hash_ref to create_read_dbh

0.39 Tue Dec 06 03:10:00
	- Made this available for files without .bdb

0.38 Sun Dec 06 03:55:00
	- Updated document

0.37 Sun Dec 06 02:41:00
	- Updated document

0.36 Sun Dec 06 02:20:00
	- Made BerkeleyDB's constants available directly

0.35 Sun Dec 05 23:50:00
	- Updated document

0.34 Sun Dec 05 22:00:00
	- Updated document

0.33 Sun Dec 05 19:00:00
	- Added clear_bdb_home()
	- Added support of transaction

0.31 Mon Aug 16 05:00:00
	- Added record_error($msg) which records error to /tmp/bdb_error.log

0.31 Wed Jul 21 16:47:00 2010
	- Fixed the bug of rmkdir($bdb_dir) for create_write_dbh

0.29 Thu Dec 03 09:40:00 2009
	- Fixed the bug of Cachesize in create_env()

0.28 Wed Dec 03 19:30:00 2009
	- Updated document for CPAN

0.27 Wed Dec 03 18:30:00 2009
	- make test removes bdb files and home directories created by itself

0.26 Wed Dec 02 15:30:00 2009
	- Added LockDetect function to create_env();
	- Added cache and no_lock option to create_env() and create_write_dbh(). It will overwrite the value specified in new()
	- Updated the example code
	- Added the comment which method is not recommended one now.

0.25 Fri Aug 07 17:10:00 2009
	- Bug fix about no_env option of create_write_dbh

0.24 Sun Nov 30 13:00:00 2008
	- {'bdb'=>$bdb} option became available for create_write_dbh and so on.

0.23 Sat Nov 01 22:00:00 2008
	- new api get_bdb_home($BDB) was added.

0.22 Mon Oct 27 23:00:00 2008
	- create_write_dbh now can creates bdb without mkdir for bdb.
	- modified the behavior of how to remove dead lock

0.21 Mon Oct 20 23:00:00 2008
	- Added dependency of BerkeleyDB.pm to Makefile.PL

0.20 Sun Oct 19 03:00:00 2008
	- Fixed the bug of {'sort_num'=>1}
	- Fixed the behaviour about how to react to the dead lock
	- Removed the part which creates the warning "Use of uninitialized value in string"

0.18  Sat Sep 06 04:30:00 2008
        - no_log parameter was added for new BDB::Wrapper({'no_log'=>1 or 0(default)})
If you set {'no_lock'=>1}, the control of concurrent access will not be used. So the lock files are also not created.

0.17  Fri Sep 05 07:00:00 2008
        - cache parameter was added for new BDB::Wrapper({'cache'=>$CACHE_SIZE})
If you set {'cache'=>$CACHE_SIZE}, you can allocate cache memory of the specified bytes for using bdb files.

0.16  Mon Jul 01 10:00:00 2008
	- Document was modified.

0.15  Mon Jul 01 07:00:00 2008
	- Document was modified.

0.14  Mon Jul 01 03:00:00 2008
	- Document was modified.

0.13  Mon Jun 30 20:00:00 2008
	- new method now supports 'wait' option for specifing the time in which dead lock will be removed.
	- Document was modified.

0.12  Tue Jun 24 16:00:00 2008
	- create_read_dbh, create_read_hash_ref now have the unlock function for dead lock
	- Potential bug was fixed.
	- Document was modified.

0.11  Tue Jun 17 23:00:00 2008
	- sort, sort_num and reverse_num is now available for btree.
	- Document was modified.

0.10  Mon Jun 09 18:40:00 2008
	- sort_code_ref, reverse and reverse_cmp is now available for btree.
	- minor bug was fixed.

0.01  Wed Apr 16 07:17:14 2008
	- original version; created by h2xs 1.23 with options
		-A -X -b 5.6.0 -n BDB::Wrapper