Path: utzoo!utgpu!watserv1!watmath!att!tut.cis.ohio-state.edu!snorkelwacker!usc!wuarchive!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.unix.questions
Subject: Re: signal trapping
Message-ID: <13799@smoke.BRL.MIL>
Date: 10 Sep 90 15:27:48 GMT
References: <5423@munnari.oz.au>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 12

In article <5423@munnari.oz.au> darrenr@mullauna.cs.mu.OZ.AU (Darren REED) writes:
>Hi, how do I go about detecting when a user quits a program by dropping their
>connection via a network ?

If the networking support is any good, you should get a SIGHUP.

>Also, is it possible to write a signal handler for a SIGKILL which gets
>executed when a SIGKILL is received but doesn't stop the impending death ?

No, SIGKILL cannot be caught or ignored (as the manual says!)
SIGKILL is normally sent only as a last resort; SIGTERM is considered
a better way to try to kill a process.  SIGTERM can be caught.