Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!lll-winken!uunet!virtech!cpcahil
From: cpcahil@virtech.UUCP (Conor P. Cahill)
Newsgroups: comp.unix.questions
Subject: Re: What is a process group
Message-ID: <1291@virtech.UUCP>
Date: 20 Oct 89 01:46:29 GMT
References: <1158@msa3b.UUCP>
Organization: Virtual Technologies Inc
Lines: 20

In article <1158@msa3b.UUCP>, kevin@msa3b.UUCP (Kevin P. Kleinfelter) writes:
> I have inherited some code which does
> 	pid = setpgrp ();
> 	ioctl (2, TIOCSPGRP, &pid);
> to change the process group on the terminal.  Why would someone want to
> do this?

The main purpose for changing the process group (and disconnecting from the 
tty -- the ioctl()) is to allow a background/daemon process to continue
running without being affected by operations happening on the tty from 
which the process started.  Like the user loggin out, which will normally 
send a SIGHUP to all processes associated with the terminal.



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| Conor P. Cahill     uunet!virtech!cpcahil      	703-430-9247	!
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