Re: Cross-platform availability of header files

[Russ Allbery]

Zack Weinberg <address@hidden> writes:

> I think we should try to come up with a principled cutoff for how old is
> too old, though. I started this thinking POSIX.1-2001 (including XSI,
> but maybe not any other options) was a reasonable place to draw the
> line, but it turns out Android omits a bunch of that (and not the old
> junk either) so it's not so simple.

> "You can assume a C89 hosted environment" does still seem like a sound
> assertion, though.

It's also important not to exclude Windows, which sometimes is missing
some things that are otherwise universal.  Autoconf can't probe on Windows
*directly* (without using one of the UNIX-like portability shells, which
often provide the missing bits as well), but the fact that Autoconf
generates the conditionals (in config.h for example) is still extremely
useful in combination with a hand-written config.h.win that's used by
Windows MSVC builds.

(ssize_t was the thing I ran into most recently that Windows doesn't have
but which is otherwise universal and required by POSIX.)

-- 
Russ Allbery (address@hidden)             <http://www.eyrie.org/~eagle/>