NAME

IPC::Lockfile - run only one instance of a program at a time using flock

VERSION

version 0.05

SYNOPSIS

Just import the module:

    #!/usr/bin/env perl
    use IPC::Lockfile;

    ... # program code here

This will open a lock on the program file, avoiding the need for an external lockfile. This elegant solution for lockfiles was proposed by Mark Jason Dominus.

DESCRIPTION

IPC::Lockfile is a module for use with Perl programs when you only want one instance of the script to run at a time. It uses flock and should work if run on an OS that supports flock (e.g. Linux, BSD, OSX and Windows).

SEE ALSO

Sys::RunAlone for a more flexible module that uses the same technique as IPC::Lockfile

My PerlTricks.com article about this solution.

IPC::Pidfile for a PID-based solution that relies on signals and has a race condition (not recommended).

AUTHOR

David Farrell <dfarrell@cpan.org>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2015 by David Farrell.

This is free software, licensed under:

  The (two-clause) FreeBSD License