Move some *at definitions to syscalls.list (bug 14138)

[Joseph S. Myers]

On Tue, 30 Sep 2014, Rich Felker wrote:

> On Mon, Sep 29, 2014 at 11:16:32PM +0000, Joseph S. Myers wrote:
> > Continuing the move of syscall definitions to syscalls.list, where the
> > removal of support for old kernel versions has made this possible,
> > this patch moves definitions of various *at functions in
> > sysdeps/unix/sysv/linux/.
> 
> I think this is premature. Some of these functions, especially
> fchmodat, have serious bug reports open against them which cannot be
> fixed if they're pure syscall wrappers. See:
> 
> https://sourceware.org/bugzilla/show_bug.cgi?id=14578

My patch did not change fchmodat because the implementation isn't simply a 
syscall wrapper (the C function has an extra argument).  For anything 
that's currently a syscall wrapper in glibc, there is no point in it being 
a C wrapper rather than a syscalls.list entry simply because some future 
change might require such a wrapper; it can be converted to C at the point 
where a C implementation is needed.

-- 
Joseph S. Myers
joseph@codesourcery.com