fchmod
======

POSIX specification:
 https://pubs.opengroup.org/onlinepubs/9699919799/functions/fchmod.html

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  * This function is missing on some platforms: mingw, MSVC 14.

  * This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).