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This documentation is no longer maintained.  For more information about mozprocess as part of the mozbase project, please see the mozbase project page.

mozprocess provides python process management via an operating system and platform transparent interface to Mozilla platforms of interest. Mozprocess aims to provide the ability to robustly terminate a process (by timeout or otherwise), along with any child processes, on Windows, OS X, and Linux. Mozprocess utilizes and extends subprocess.Popen to these ends.


mozprocess.processhandler:ProcessHandler is the central exposed API for mozprocess. ProcessHandler utilizes a contained subclass of subprocess.Popen, Process, which does the brunt of the process management.

Basic usage:

process = ProcessHandler(['command', '-line', 'arguments'],
                         cwd=None, # working directory for cmd; defaults to None
                         env={},   # environment to use for the process; defaults to os.environ
exit_code = process.waitForFinish(timeout=60) # seconds

See an example in

ProcessHandler may be subclassed to handle process timeouts (by overriding the onTimeout() method), process completion (by overriding onFinish()), and to process the command output (by overriding processOutputLine()).


  • Document improvements over subprocess.Popen.kill

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 Contributors to this page: teoli, jhammel
 Last updated by: jhammel,