From: "Damian Yerrick" <NOSP AT Msnews@pineight.8m.com>
Newsgroups: comp.os.msdos.djgpp
References: <Pine DOT SUN DOT 3 DOT 91 DOT 1000102112005 DOT 1710e-100000 AT is>
Subject: Re: system() hangs or returns incorrect value when child process killed
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NNTP-Posting-Date: Sun, 02 Jan 2000 22:16:48 GMT
Distribution: world
Date: Sun, 02 Jan 2000 22:16:48 GMT
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il> wrote:
> On Sun, 2 Jan 2000, Steve Ball wrote:
>
> > Does anyone know a workaround for this bug?
>
> I didn't see any bugs in what you describe.  It's all expected
> behavior.

Or as Micro$oft Knowledge Base states it:
"This behavior is by design." It's not a bug; it's a feature.

> > If the child process is killed using ^C or ^-Break, system() should
return a
> > value with SIGINT in bits 8-17.
>
> Ideally, yes; but it doesn't always work.  DOS is very inconsistent in
> this aspect, especially since many programs catch ^C and ^BREAK and do
> custom things before they exit.

And some programs:
1. catch Ctrl+C and make it copy the selection to the clipboard or
2. catch all keys in a custom key interrupt handler. (Most Allegro
programs do this.)

> In general, pressing ^C while the child program runs delivers the
> signal SIGINT to its parent(s) as well, so the parent doesn't need to
> do anything to terminate: it will be aborted automatically once the
> child exits.

So if a program catches SIGINT and maps it to Edit > Copy,
then it will abort the parent when it's done?

--
Damian Yerrick    http://yerricde.tripod.com/
View full .sig:  http://www.rose-hulman.edu/~yerricde/sig.html










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