accept4
-------

Documentation:
 man accept4

Gnulib module: accept4

Portability problems fixed by Gnulib:

  * This function is missing on many non-glibc platforms: glibc 2.9, macOS 11.1, FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 11.3, Cygwin 1.7.1, mingw, MSVC 14, Android 4.4. But the replacement function is not atomic; this matters in multi-threaded programs that spawn child processes.

Portability problems not fixed by Gnulib:

  * SOCK_CLOEXEC and SOCK_NONBLOCK may not be defined as they're also significant to the socket() function.