shmat
=====

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

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  * This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

  * On Linux, the flag SHM_REMAP is needed in order to force shmat to replace existing memory mappings in the specify address range.  On other platforms, it is not needed.