perror() changes the orientation of stderr to byte-oriented mode if stderr is not oriented yet.

[Andreas Köpke]

ah sorry -- unistd.h works. 

> Hi,
> 
> On Thu, 5 Jul 2018 13:38:52 +0200
> 
> Andreas Köpke wrote:
> > I'm working on bare metal using newlib - with the changes to perror it
> > does
> > not compile anymore: none of the headers (sys/uio.h, unistd.h) are known.
> 
> Bare metal does not have not only sys/uio.h but also unistd.h?
> It seems a few stdio files includes unistd.h at least for several
> months ago.