From: Michal Suchánek <msuchanek@suse.de>
Date: Sun, 05 Jan 2020 15:27:32 GMT
Subject: Re: ERANGE strikes again on my Windows build; RFH
Message-ID: <20200105152732.GR4113@kitsune.suse.cz>
In-Reply-To: <20191230184948.GC57251@google.com>

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