_longjmp
========

POSIX specification: http://www.opengroup.org/onlinepubs/9699919799/functions/_longjmp.html

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  * This function is missing on some platforms: Solaris 2.5.1, mingw.

Note: A future revision of POSIX later than the 2008/2009 one may drop the functions _setjmp and _longjmp.  Still, in 2008, on all systems which have _setjmp, it is the fastest way to save the registers but not the signal mask (up to 30 times faster than setjmp on some systems).