NAME

Genezzo::Contrib::Clustered::GLock::GLockDLM - OpenDLM locking implementation for Genezzo

SYNOPSIS

my $lockid = dlm_lock($name, $shared, $blocking);
my $success = dlm_promote($name, $lockid, $blocking);
my $success = dlm_unlock($lockid);

DESCRIPTION

Provides Perl wrappers to basic OpenDLM C functions.

FUNCTIONS

dlm_lock NAME, SHARED, BLOCKING

Locks lock with name NAME. Shared if SHARED=1, otherwise exclusive. Blocking if BLOCKING=1, otherwise returns immediately. Returns lockid,or 0 for failure.

dlm_promote NAME, LOCKID, BLOCKING

Promotes lock with name NAME and lockid LOCKID to exclusive mode. Returns 1 for success, or 0 for failure.

dlm_demote NAME, LOCKID, BLOCKING

Demotes lock with name NAME and lockid LOCKID to shared mode. Returns 1 for success, or 0 for failure.

dlm_unlock LOCKID

Releases lock with lockid LOCKID. Returns 1 for success, 0 for failure.

dlm_ast_poll

Returns 1 if recent asyncronous request for lock held by process. 0 otherwise.

EXPORT

dlm_lock, dlm_promote, dlm_unlock

LIMITATIONS

Relies on Perl Inline::C module. Requires OpenDLM be installed. Currently terminates program when deadlock detected.

AUTHOR

Eric Rollins, rollins@acm.org

SEE ALSO

http://opendlm.sourceforge.net/docs.php.

Copyright (c) 2005 Eric Rollins. All rights reserved.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

Address bug reports and comments to rollins@acm.org

For more information, please visit the Genezzo homepage at http://www.genezzo.com