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Date: Tue, 25 Nov 1997 15:45:01 -0800
From: Julian Elischer <julian@whistle.com>
Organization: Whistle Communications
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To: Charles Mott <cmott@srv.net>
CC: Terry Lambert <tlambert@primenet.com>, freebsd-hackers@freebsd.org
Subject: Re: pthread_cond_timedwait returning wrong error?
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Charles Mott wrote:
> 
> On Tue, 25 Nov 1997, Terry Lambert wrote:
> > > > While we are talking about threads, any comments on PR-4376?
> > >
> > > You are 100% right about the return value being incorrect.
> > > Unfortunately, this problem is present in many more functions than just
> > > pthread_join().
> > >
> > > From what I can tell by looking at an old DEC OSF/1 reference on
> > > pthreads, returning -1 an setting errno is the way things used to work.
> > > Apparently POSIX has changed that.
> >
> > Given that "errno" is a global variable, this is actually a good thing.
> >
> 
> I was wondering whether maybe errno could be a thread-specific variable
> rather than global -- mabye via use of a macro.  I was looking through
> libc_r sources, but I couldn't discern what was being done in this regard.
> 
> To me, having all the *_r reentrant functions is a big nuisance.
> 
> Charles Mott

errno is defined in threads systems as:
errno[thread_number]
or similar tricks..