getsockopt
==========

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

LSB specification:
 https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getsockopt-1.html

Gnulib module: getsockopt

Portability problems fixed by Gnulib:

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

  * On HP-UX 11, in 64-bit mode, when the macro _HPUX_ALT_XOPEN_SOCKET_API is not defined, this function behaves incorrectly because it is declared to take a pointer to a 64-bit wide socklen_t entity but in fact considers it as a pointer to a 32-bit wide unsigned int entity.

Portability problems not fixed by Gnulib:

  * Some platforms don't have a socklen_t type; in this case this function's fifth argument type is int *.

  * Many socket options are not available on all platforms.