Unexpected EOF handling

[Tomas Mraz]

On Thu, 2020-05-07 at 15:45 +0200, Kurt Roeckx wrote:
> On Thu, May 07, 2020 at 03:15:22PM +0200, Tomas Mraz wrote:
> > Actually the coincidence is that the errno is set to 0 on EOF. So
> > yes,
> > we should explicitly clear the errno on EOF so any leftover value
> > from
> > previous calls does not affect this.
> 
> On EOF, errno is normally not modified. It's value is not defined
> if no error is returned. It is not guaranteed to be 0 on success
> or EOF. It can be modified, because the implementation might have
> done other system calls that did return an error. But a simple test
> shows that it's not modified on my system.
> 

Yeah, that's what I actually meant, sorry for not being clear. I did
not mean that the errno is explicitly set to 0 on EOF by the read call
but that the errno is 0 because it is not modified and was 0 before
coincidentally. 

-- 
Tomáš Mráz
No matter how far down the wrong road you've gone, turn back.
                                              Turkish proverb
[You'll know whether the road is wrong if you carefully listen to your
conscience.]