5 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/popen.html}
9 Portability problems fixed by Gnulib:
12 This function is missing on some platforms:
15 Some platforms start the child with closed stdin or stdout if the
16 standard descriptors were closed in the parent:
20 Portability problems not fixed by Gnulib:
23 On native Windows platforms, this functions terminates the current process
24 with exit code 127 if the environment variable @code{COMSPEC} is not set.
26 Some platforms mistakenly set the close-on-exec bit, then if it is
27 cleared by the application, the platform then leaks file descriptors
28 from earlier @code{popen} calls into subsequent @code{popen} children: