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From: dave@rsch.wisc.edu (Dave Cohrs)
Newsgroups: net.unix
Subject: Re: How to allow one process to talk to tty while stty tostop?
Message-ID: <2868@rsch.WISC.EDU>
Date: Mon, 27-Oct-86 12:48:54 EST
Article-I.D.: rsch.2868
Posted: Mon Oct 27 12:48:54 1986
Date-Received: Mon, 27-Oct-86 22:28:12 EST
References: <1979@well.UUCP>
Sender: news@rsch.WISC.EDU
Reply-To: dave@rsch.wisc.edu (Dave Cohrs)
Organization: U of Wisconsin CS Dept
Lines: 21
Keywords: tty, stty tostop

In <1979@well.UUCP> rlw@well.UUCP (Bob Weissman) writes:
> I have a background process I would like to be able to write to the tty
> while `stty tostop' is in effect.  Is this possible, and if so, how do
> ya do it?

It's possible, and it's even easy.  When "tostop" is set, a process
gets sent a SIGTTOU signal if it tries to write to the tty and it's
not in the current process-group for the tty.  The SIGTTOU stops the
process.

The easiest way to keep from stopping is to insert the line:

	signal(SIGTTOU, SIG_IGN);

somewhere in your "unstoppable" program before it prints anything.

--
Dave Cohrs
(608) 262-1204
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