NAME

IPC::Pidfile - run only one instance of a program at a time

VERSION

version 0.02

SYNOPSIS

Just import the module:

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

  ... # program code here

This will create a pidfile for the program and clear it up when the program is finished.

DESCRIPTION

IPC::Pidfile is a module for use with Perl programs when you only want one instance of the script to run at a time. It should work for you if:

  • You are OK with the pidfile being created in the same directory as the script

  • You are not using an obscure OS. (Linux, BSD, OSX and Windows should be OK, see CPANTESTERS).

  • Your program is not using signal handlers for SIGINT and SIGTERM. IPC::Pidfile uses these to clear up the pidfile at the end of the process

WARNING

This module has a race condition as it attempts to remove the pidfile. It might be better to use IPC::Lockfile.

BUGS/ISSUES

Race condition (see #WARNING).

This is an early release and may contain bugs. To run IPC::Pidfile in debug mode, create the environment variable IPC_PIDFILE_DEBUG:

  IPC_PIDFILE_DEBUG=1 ./path/to/program

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