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To: imp@village.org
cc: freebsd-hackers@FreeBSD.ORG
Subject: select(2) timeval
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Date: Wed, 18 Oct 1995 08:20:55 -0500
From: Jon Loeliger <jdl@chrome.onramp.net>
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> : > In addition, the select(2) call in BSD reserves the right to modify the
> : > timeval structure to indicate the remaining time to allow the use of
> : > the timeout as an even outcall mechanism for logical multithreading.
> 
> As someone who ported an application that depended on select(2) not
> doing that, I can tell you that only Linux will really change the
> value of timeval in a select call.  If that is not correct, I'd like
> to know who else does change it (rather than merely reserve the right
> to change it).

As a point of reference, about a year ago, I wrote a time-based delta
queue application under AIX.  As I recall, it's BSD interface did NOT
adjust the timeval in a select() call, and so I ended up having to
compensate for it in my code.

jdl