Author martius
Recipients martius
Date 2016-09-27.14:26:42
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Currently, subprocess.Popen performs blocking IO in its constructor (at least on Unix): it reads on a pipe in order to detect outcome of the pre-exec and exec phase in the new child. There is no way yet to modify this behavior as this blocking call is part of a long Popen._execute_child() method.

This is a problem in asyncio (asyncio.subprocess_exec and asyncio.subprocess_shell).

I would like to submit a patch which breaks Popen.__init__() and Popen._execute_child() in several methods so it becomes possible to avoid blocking calls (read on pipe and waitpid) by overriding a few private methods without duplicating too much code. The goal is to use it in asyncio, as described in this pull request (which currently monkey-patches Popen):

This patch only targets the unix implementation.

Thanks for your feedback.
Date User Action Args
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