[New-bugs-announce] [issue32859] os.dup2() tests dup3() availability on each call

[Alexey Izbyshev]

New submission from Alexey Izbyshev <izbyshev at ispras.ru>:

os.dup2() tests for dup3() system call availability at runtime, but doesn't remember the result across calls, repeating the test on each call with inheritable=False even if the test fails.

Judging by the code, 'dup3_works' was intended to be static (the first time its value is checked it's always an initial one).

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components: Extension Modules, Library (Lib)
messages: 312256
nosy: benjamin.peterson, izbyshev, vstinner
priority: normal
severity: normal
status: open
title: os.dup2() tests dup3() availability on each call
type: performance
versions: Python 3.6, Python 3.7

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue32859>
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