process.py is a (rather large) Python module to make process control easier and more consistent on Windows, Linux, and Mac OS X (and other Un*ces). The current mechanisms (os.popen*, os.system, os.exec*, os.spawn*) all have limitations.

A quick list of some reasons to use process.py:

• You don't have to handle quoting the arguments of your command line. You can pass in a command string or an argv.
• You can specify the current working directory (cwd) and the environment (env) for the started process.
• On Windows you can spawn a process without a console window opening.
• You can wait for process termination or kill the running process without having to worry about weird platform issues. (Killing on Windows should first give the process a chance to shutdown cleanly. Killing on Linux will not work from a different thread than the process that created it.)
• The ProcessProxy class allows you to interact in a pseudo-event-based way with the spawned process. I.e., you can pass in file-like object for any of stdin, stdout, or stderr to handle interaction with the process.

Project Status

Since I originally developed process.py, Python has grown (in version 2.4) the new subprocess module. I haven't done a feature comparison of process.py and subprocess but the latter is definitely more capable than the older Python process control mechanisms. If you are considering using process.py you should definitely checkout subprocess as well.

It has been over 3 years since this module has been maintained. In its current state it was used heavily in the commercial Komodo IDE project. However, since 2007 a significant overhaul of process.py used in Komodo was undertaken. Komodo's process module is now a (rather heavily) tweaked wrapper around Python's core subprocess module. See the process modules in the open source Komodo Edit source tree here. The process modules are the same as those used in Komodo IDE.

Despite this module not having been maintained, there are still somethings of value in here. Esp. regarding the guts of some process control from Python on Windows. Gross stuff. Mostly this project is here for reference.

Python process control links

TODO: links for the following

• core subprocess module
• svn.openkomodo.com's process.py module above
• Benjamin Smedberg's killable-process-from-python blog post