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From: lihuiba <magazine.lihuiba@163.com>
To: libc-help@sourceware.org
Subject: a question about the implementation of errno
Date: Wed, 04 Jul 2018 05:07:00 -0000	[thread overview]
Message-ID: <19bfad75.513b.16463b06140.Coremail.magazine.lihuiba@163.com> (raw)

Hi all,


I noticed recently that errno is implemented as a macro that expands to (*__errno_location()).
I wonder why it is implemented as this, and why it is not a thread-local int variable.
I suppose thread-local int is faster than function all.


Thanks!




Huiba Li

             reply	other threads:[~2018-07-04  5:07 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-04  5:07 lihuiba [this message]
2018-07-04 10:35 ` Florian Weimer
2018-07-04 11:34   ` lihuiba

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