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A backport of the Python 3 subprocess module for use on Python 2.
Python C M4 Shell
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This is a backport of the Python 3 subprocess module for use on Python 2. This code has not been tested on Windows or other non-POSIX platforms.

subprocess32 includes many important reliability bug fixes relevant on POSIX platforms. The most important of which is a C extension module used internally to handle the code path between fork() and exec(). This module is reliable when an application is using threads.

Refer to the Python 3.5 subprocess documentation for usage information.

  • Timeout support backported from Python 3.3 is included.
  • The run() API from Python 3.5 was backported in subprocess32 3.5.0.
  • Otherwise features are frozen at the 3.2 level.


The recommend pattern for cross platform code is to use the following:

if == 'posix' and sys.version_info[0] < 3:
    import subprocess32 as subprocess
    import subprocess

Or if you fully control your POSIX Python 2.7 installation, this can serve as a replacement for its subprocess module. Users will thank you by not filing concurrency bugs.

Got Bugs?

Try to reproduce them on the latest Python 3.x itself and file bug reports on Add gregory.p.smith to the Nosy list.

If you have reason to believe the issue is specifically with this backport and not a problem in Python 3 itself, use the github issue tracker.

-- Gregory P. Smith

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