Re: Namespace issues, missing functions, _BSD_SOURCE for unistd.h

[Isaac Dunham <idunham@lavabit.com>]

> There is no "ANSI" namespace in unistd.h because it's not a standard C
> header but a POSIX header. It's definitely correct for POSIX 2008 base
> as-is without any patching.
Should have checked that. 
I guess it will be a rewrite then.

Which profiles are you aiming to support? Latest versions only for
POSIX, ISO, and X/Open? Or only versions in the past decade?
I don't see any signs of  version checks, so I assume you want POSIX2008
and XOPEN2008 (_XOPEN_SOURCE >= 700) only, and no support for SUSv3.
This will make the patch a lot smaller and cleaner.

> > BSD || XOPEN means the macro test should be
> > #if defined(_BSD_SOURCE) || defined(_XOPEN_SOURCE)
> > I see glibc turns on both of these with _GNU_SOURCE.
> Yes, I think you overlooked some of the logic of how glibc's
> features.h works...
Tried to decode it, but it's pretty easy to lose track (especially in
the ifdef nest that handles XOPEN_SOURCE).

> > Misplaced (should be BSD || XOPEN):
> > (Properly, these require XOPEN >= 500)
> > usleep, ualarm, fchown, fchdir, lchown,vhangup,
> > apparently fsync? 
> All incorrect.
> usleep and ualarm were removed by SUSv4/POSIX 2008 and thus do not
> belong in any profile except ones with nonstandard extensions.
> fchown, fchdir, and lchown are all POSIX 2008 base.
> vhangup was perhaps standard at one time but removed
OK. _GNU_SOURCE || _BSD_SOURCE
It's _XOPEN_SOURCE == 500 || 600, which I take it will not be supported.

<snip>
> AFAIK most of these do not exist in musl at the moment.
Guessed that.  It was meant as a comment on the status.

> > BSD||GNU:
..
 
> > +#if defined(_BSD_SOURCE) && !defined(L_SET)
> > +#define L_SET
> > +#define L_INCR
> > +#define L_XTND
> > +#endif
Forgot to add the SEEK_SET, etc. here.
Should be 
#define L_SET SEEK_SET
..
hence the placement.
 
> > +#if !( (_POSIX_SOURCE - 0) < 200112L )
> > +int seteuid(uid_t);
> > +int setegid(gid_t);
> > +#endif
> 
> I have no intention of trying to make a profile that conforms to the
> 1990 version of POSIX.
Forgot they went from straight from 1993 to 2001; I'll take that test
out. 

> 
> > +#if defined(_BSD_SOURCE) || ...
 
> > +pid_t vfork(void);
> > +int vhangup(void);
> > +int usleep(unsigned);
> > +unsigned ualarm(unsigned, unsigned);
> 
> And these do not exist in SUSv4. (The first two are not in SUSv3
> either.)
Will fix.

Thanks for the comments.
Isaac Dunham