ioctl
=====

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

Gnulib module: ioctl

Portability problems fixed by Gnulib:

  * On Windows platforms (excluding Cygwin), ioctl is called ioctlsocket, and error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

  * The second parameter is of type unsigned long rather than int on some platforms: glibc 2.26, Mac OS X 10.5, FreeBSD 11.0, NetBSD 7.0, OpenBSD 6.0, Haiku 2017.

Portability problems not fixed by Gnulib:

  * Most ioctl requests are platform and hardware specific.