Re: [PATCH] Various pages: Remove unused <sys/types.h>

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

Hello Zack,

On Sun, 14 Mar 2021 at 22:40, Zack Weinberg <zackw@panix.com> wrote:
>
> On Sun, Mar 14, 2021 at 12:04 PM Alejandro Colomar via Libc-alpha
> <libc-alpha@sourceware.org> wrote:
> >
> > The manual pages are already inconsistent in which headers need
> > to be included.  Right now, not all of the types used by a
> > function have their required header included in the SYNOPSIS.
> >
> > If we were to add the headers required by all of the types used by
> > functions, the SYNOPSIS would grow too much.  Not only it would
> > grow too much, but the information there would be less precise.
> >
> > Having system_data_types(7) document each type with all the
> > information about required includes is much more precise, and the
> > info is centralized so that it's much easier to maintain.
> >
> > So let's document only the include required for the function
> > prototype, and also the ones required for the macros needed to
> > call the function.
>
> I endorse this change.

I agree. Do you want to add an "Acked-by:"?

Thanks,

Michael

> For glibc, if the header file containing the
> function prototype doesn't also provide everything you need to call
> the function, it's a bug (except for a few cases where the relevant
> standards prevent us from doing this, e.g. a function that calls
> vprintf will need the macros in <stdarg.h>, but the C standard
> specifically forbids <stdio.h> to include <stdarg.h>).
>
> > <sys/types.h> only defines types, not functions or constants, so
> > it doesn't belong to man[23] (function) pages at all.
> > I ignore if some old systems had headers that required you to
> > include <sys/types.h> *before* them (incomplete headers),
>
> Such systems did exist in the past, but they are too old to worry
> about nowadays.  I don't think it's possible for them to be compliant
> with POSIX.1-1995, and the examples I know of personally (SunOS 4, for
> instance) were not even fully compliant with C89.




-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/