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PEP 446: cleanup recent additions

This commit is contained in:
Victor Stinner 2013-08-07 01:49:59 +02:00
parent 62767d3960
commit 79d319c3b6
1 changed files with 8 additions and 7 deletions
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pep-0446.txt
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@ -285,17 +285,18 @@ Legend:
Performances of Closing All File Descriptors
--------------------------------------------
On UNIX, the subprocess module closes almost all file descriptors in the
child process. This operation require MAXFD system calls where MAXFD is
the maximum number of file descriptors, even if there are few open file
descriptors. This maximum can be get using: ``sysconf("SC_OPEN_MAX")``.
On UNIX, the ``subprocess`` module closes almost all file descriptors in
the child process. This operation require MAXFD system calls, where
MAXFD is the maximum number of file descriptors, even if there are only
few open file descriptors. This maximum can be read using:
``sysconf("SC_OPEN_MAX")``.
The operation can be slow if MAXFD is large. For example, on a FreeBSD
buildbot with ``MAXFD=655,000``, the operation took 0.3 second: see
buildbot with ``MAXFD=655,000``, the operation took 300 ms: see
`issue #11284: slow close file descriptors
<http://bugs.python.org/issue11284#msg132668>`_).
<http://bugs.python.org/issue11284#msg132668>`_.
On Linux, Python gets the list of all open file descriptors from
On Linux, Python 3.3 gets the list of all open file descriptors from
``/proc/<PID>/fd/``, and so performances depends on the number of open
file descriptors, not on MAXFD.