From: jjenning@... (jared l. jennings)
Date: 2002-05-07T04:00:19+09:00
Subject: fork + socket = hang

i've got a program (interesting, but description lengthy) which accepts
commands over socket connections. Here's a typical little transcript:

nc localhost 1542
[recv] PLD G2 awaits your command.
[recv] .
[recv]
[send] genre: misc
[send] start_ices
[recv] Started /usr/bin/ices -c /etc/ices/misc.ices.conf
[recv] .
[recv]
       [connection hangs]

With other commands that don't involve forking and execing, i can send
"close" and the server will close the connection. But with commands
involving forking/execing (it was system before, but i copied stuff from
this last thread about defunct processes), the connection hangs. I have
to just ^C out of netcat and wait for the connection to time out on the
other end. I surmise this hanging is because the child process gets all
the open files (and sockets) in the fork{}, and closes them when it ends
(because ices promptly forks off and exits).

how do i keep this from happening?