/ 
Dev-Util-v2.19.11
/ Dev::Util::Sem

NAME

Dev::Util::Sem - Module to do Semaphore locking

VERSION

Version v2.19.11

SYNOPSIS

To ensure that only one instance of a program runs at a time, create a semaphore lock file. A second instance will wait until the first lock is unlocked before it can proceed or it times out.

use Dev::Util::Sem;

my $sem = Sem->new('mylock.sem');
...
$sem->unlock;

EXPORT

new
unlock

METHODS

new

Initialize semaphore. You can specify the full path to the lock, and if the directory you specify exists and is writable then the lock file will be placed there. If you don't specify a directory or the one you specified is not writable, then a list of alternate lock dirs will be tried.

my $sem1 = Sem->new('/wherever/locks/mylock1.sem');
my $sem2 = Sem->new('mylock2.sem', TIMEOUT);

TIMEOUT number of seconds to wait while trying to acquire a lock. Default = 60 seconds

Alternate lock dirs:

qw(/var/lock /var/locks /run/lock /tmp);

unlock

Unlock semaphore and delete lock file.

$sem->unlock;

AUTHOR

Matt Martini, <matt at imaginarywave.com>

BUGS

flock may not work over nfs.

Please report any bugs or feature requests to bug-dev-util at rt.cpan.org, or through the web interface at https://rt.cpan.org/NoAuth/ReportBug.html?Queue=Dev-Util. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc Dev::Util::Backup

You can also look for information at:

ACKNOWLEDGMENTS

LICENSE AND COPYRIGHT

This software is Copyright © 2001-2025 by Matt Martini.

This is free software, licensed under:

The GNU General Public License, Version 3, June 2007