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PidFileA basic library for creating lockfiles for processes
This library works with Ruby 1.8 and 1.9 and is licensed under the MIT License.
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InstallationThe pidfile gem is hosted on RubyGems.org (rubygems.org). This requires that you have rubygems.org in your gem sources.
Install the pidfile gem:
sudo gem install pidfile
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Gettings StartedThe pidfile gem is easy to use and only requires the instantiation of the pidfile, like so:
pf = PidFile.new
Of course there is other functionality, but if you are just wanting to keep a process from running more than once, this is all you need.
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ArgumentsPidFile creates file to store the process ID (PID). By default, process ID (PID) files are created in /tmp upon instantiation and are given the same name as the calling script with a .pid extension. Process ID files are removed when the creating program exits.
Each argument, :pidfile and :piddir, can be changed upon instantiation of the class.
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Example:PidFile.new(:piddir => '/var/lock', :pidfile => "awesome.pid")
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Miscellaneous¶ ↑
Why isn’t this a singleton?My main concern is how it would behave when a process is forked multiple times. Each new process would get its own PID, but I wasn’t sure how using a singleton would affect this; if the interrelationship of the processes would keep the object from correctly identifying the correct pidfile.
Anyway, I like the flexibility that not using a singleton offers, and I guess I’d rather ask you not to do something bad rather than restraining you.
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CopyrightCopyright© 2010 Samuel Mullen (samullen). See LICENSE for details