sys/un.h
========

POSIX specification:
 https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_un.h.html

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

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

  * This header requires <code>sys/socket.h</code> to be included first on some platforms: Cygwin 1.7.18.