NAME

App::single - An application to run a single instance of a command

VERSION

0.03

DESCRIPTION

App::single is an application which allow you to run a single instance of a command. Example usage is from a cron:

* * * * * /usr/local/bin/single autossh example.com sleep 86400 2>/dev/null 1>/dev/null

The way it works is that it makes a temporarily file which include information about the process. Information written to the file includes the PID of the process, so the second time single is started with the same arguments it will check if the PID is alive.

NOTE: This script is not atomic, but more than good enough for handling the "crontab" case.

SYNOPSIS

$ single <command>
$ single autossh example.com sleep 864000
$ single "echo 123;sleep 86400";

NOTE: Including shell characters (such as ">", "|", ";", ...) will invoke the shell, allowing unsafe user input.

INSTALLATION

The easiest way to get this application is by using cpanminus:

$ curl -L http://cpanmin.us | perl -n - --sudo App::single

Note: --sudo is to install "single" system wide, "-n" is to skip tests for faster installation.

COPYRIGHT AND LICENSE

Copyright (C) 2014, Jan Henning Thorsen

This program is free software, you can redistribute it and/or modify it under the terms of the Artistic License version 2.0.

AUTHOR

Jan Henning Thorsen - jhthorsen@cpan.org