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Date:   Sun, 5 Jan 2020 16:27:32 +0100
From:   Michal =?iso-8859-1?Q?Such=E1nek?= <msuchanek@suse.de>
To:     Jonathan Nieder <jrnieder@gmail.com>
Cc:     Johannes Sixt <j6t@kdbg.org>,
        Git Mailing List <git@vger.kernel.org>
Subject: Re: ERANGE strikes again on my Windows build; RFH
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References: <6eb02a73-9dcb-f1fc-f015-80e71e9910d6@kdbg.org>
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On Mon, Dec 30, 2019 at 10:49:48AM -0800, Jonathan Nieder wrote:
> Johannes Sixt wrote:
> > Am 30.12.19 um 19:06 schrieb Jonathan Nieder:
> 
> >>                                                                    when
> >> errno is meaningful for a function for a given return value, the usual
> >> convention is
> >>
> >>  (1) it *always* sets errno for errors, not conditionally
> >
> > You seem to understand that errno isn't set somewhere where it should be
> > set.
> 
> On the contrary: this caller is using errno as an error *indicator*
> instead of a way of *distinguishing* between errors (or to put it
> another way, this caller is treating `errno == 0` as a meaningful
> condition).  This means the calling code is buggy.

That works completely fine if the code in question also sets errno to 0
in case there is some other leftover value from a previous library call.

Thanks

Michal