tcgetsid
========

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

Gnulib module: tcgetsid

Portability problems fixed by Gnulib:

  * This function is missing on some platforms: FreeBSD 6.0, OpenBSD 4.5, Minix 3.1.8, Cygwin 1.7.9, mingw, MSVC 14, Android 4.4.

  * The declaration of this function in C++ compilation units has C++ linkage, not C linkage, on some platforms: HP-UX 11.00.

Portability problems not fixed by Gnulib:

  * This function always fails on some platforms: FreeBSD 6.0, Cygwin 1.7.8, mingw, MSVC 14.

  * This function returns int instead of pid_t on some platforms: Cygwin 1.7.11.