bug#12980: 24.3.50; Zombie process left after call-process

[Harald Hanche-Olsen]

If I run

(call-process "/bin/sleep" nil 0 nil "5")

this returns immediately (which is expected), but after 5 seconds, the
subprocess becomes a zombie and hangs around until emacs is quit.

In GNU Emacs 24.3.50.1 (x86_64-apple-darwin12.2.0, NS apple-appkit-1187.34)
 of 2012-11-09 on airy
Bzr revision: 110853 jan.h.d@swipnet.se-20121109063651-ewuwszrpta821oha
Windowing system distributor `Apple', version 10.3.1187
Configured using:
 `configure '--with-ns''

I asked about this on the emacs-devel list (see the thread "Zombie
subprocesses" starting 2012-11-23), and others report being able to
reproduce the bug on Cygwin (emacs-24 branch) and GNU/Linux
(x86_64-unknown-linux-gnu, latest emacs-24 and trunk) as well.

>From the discussion there, this appears related to bug#8855 somehow.

- Harald