The 'subprocess' Python module


subprocess is a Python module for starting and communicating with processes. This module overcomes several limitations with the old popen2 module, but also aims to be a generic module for starting and communicating with processes on POSIX systems. It can replace several older modules and functions, like: os.system, os.spawn*, os.popen*, popen2.*, and commands.*.

subprocess was called popen5 earlier.


Windows installers for this module are available from

CVS access

Anonymous CVS access

cvs login (press enter when asked for a password)
cvs co popen5

ViewCVS access

The URL for ViewCVS is


You can fetch a tarball snapshot via ViewCVS.

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