sigdelset
=========

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

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  * This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

  * This function cannot be called from plain inline or extern inline functions on some platforms: OS X 10.8.

Portability problems not fixed by Gnulib: