posix_spawn_file_actions_addclose
=================================

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

Gnulib module: posix_spawn_file_actions_addclose

Portability problems fixed by Gnulib:

  * This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

  * This function does not reject a negative file descriptor on some platforms: musl libc.

Portability problems not fixed by Gnulib: