9.233 fchmodat

POSIX specification:
http://www.opengroup.org/onlinepubs/9699919799/functions/fchmodat.html

Gnulib module: fchmodat

Portability problems fixed by Gnulib:

• This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Interix 3.5, BeOS. But the replacement function is not safe to be used in libraries and is not multithread-safe.

Portability problems not fixed by Gnulib:

• Some platforms do not allow changing the access bits on symbolic links. POSIX states that fchmodat(…,AT_SYMLINK_NOFOLLOW) may fail with EOPNOTSUPP when called on a symlink, but some platforms, as well as the gnulib replacement, fail for any use of AT_SYMLINK_NOFOLLOW even if the target was not a symlink: glibc, Cygwin.