Message-ID:	<32670863.22BE@cs.com>
Date:	Thu, 17 Oct 1996 21:32:35 -0700
From:	"John M. Aldrich" <fighteer AT cs DOT com>
Reply-To:	fighteer AT cs DOT com
Organization:	Three pounds of chaos and a pinch of salt
MIME-Version:	1.0
To:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
CC:	grendel AT ananke DOT amu DOT edu DOT pl, djgpp-workers AT delorie DOT com
Subject:	Re: Install thingy
References:	<Pine DOT SUN DOT 3 DOT 91 DOT 961017090937 DOT 24334I-100000 AT is>

Eli Zaretskii wrote:
> 
> This is incorrect.  Ctrl-Break winds up in the same signal handler as
> Ctrl-C, and therefore also causes the program to exit with the same exit
> code (unless you catch the signal, of course).  It is true that these two
> keystrokes are handled differently on a PC, but the DJGPP setup and the
> signal handling machinery take care to tunnel them both into the same
> place.  The only difference in their handling in the default handler is
> that Ctrl-Break causes a full stack trace to be printed, whereas Ctrl-C
> doesn't, but that's a feature designed to allow you to abort a stray
> program and know where did it go bananas.

I tested this last night and I am happy to say that you and Charles (who
emailed me privately) are right - Ctrl-Break is also handled as SIGINT. 
But an odd thing happened when I was testing:  if I pressed Ctrl-C, the
program exited instantly; while if I pressed Ctrl-Break, the system
would wait for another keystroke before exiting.  Is this an artifact of
using the conio functions (cgets, getch) instead of stdio?  As I recall,
when SIGINT is not handled, both keystrokes cause immediate
termination.  FYI, it happened under both Windoze and CWSDPMI.

BTW, is the fact that a generated SIGINT terminates ALL programs in an
execution chain simultaneously unless one of them handles it a feature
or a bug?  Just curious...

-- 
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| John M. Aldrich, aka Fighteer I |        fighteer AT cs DOT com          |
| Proud owner of what might one   |   http://www.cs.com/fighteer    |
| day be a spectacular MUD...     | Plan: To make Bill Gates suffer |
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