POPEN(III) in V7 Stdio

[utzoo!decvax!ucbvax!unix-wizards]

>From decvax!duke!unc!somewhere!smb at Berkeley Sun Dec 27 02:06:06 1981
In-real-life: Steven M. Bellovin

I don't much like the idea of changing something like popen, though
I confess I can't think of anything that your suggestion would break.
But let me take this opportunity to push one of my pet causes:  the
under-use of FIOCLEX, which causes an open file to be closed after
a successful exec() call.  For one thing, it closes a security hole
(does *your* version of Adventure close the cave file during a
shell escape); also, it prevents problems with programs running out
of file descriptor slots.