popen
=====

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

Gnulib module: popen

Portability problems fixed by Gnulib:

  * This function is missing on some platforms: MSVC 9.

  * Some platforms start the child with closed stdin or stdout if the standard descriptors were closed in the parent: Cygwin 1.5.x.

Portability problems not fixed by Gnulib:

  * Some platforms mistakenly set the close-on-exec bit, then if it is cleared by the application, the platform then leaks file descriptors from earlier popen calls into subsequent popen children: Cygwin 1.5.x.