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Date: Mon, 17 Dec 2001 09:39:14 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Andris Pavenis <pavenis AT lanet DOT lv>
cc: Tim Van Holder <tim DOT van DOT holder AT pandora DOT be>, djgpp-workers AT delorie DOT com
Subject: Re: Weird system() thing (was Re: The Bash 2.05 fixinc.sh bug)
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On Sun, 16 Dec 2001, Andris Pavenis wrote:

> > int
> > main(void)
> > {
> >   system("Foo=bar");
> > }
> > 
> > 
> > both, as expected, spawn a single instance of command.com, and exit
> > after
> > that shell is exited, the following does not:
> > 
> > int
> > main(void)
> > {
> >   system("");
> >   system("Foo=bar");
> > }
> 
> I guess Your executable were named foo.exe. 
>                                    ========

That could indeed explain the problem, but then why didn't the
previous example, the one with a single system("Foo=bar"), cause the
same infinite series of subprogram invocations?

> As far as I tested system ("Foo=bar") is interpretted as
> 'Foo "=bar"' 

This interpretation is in COMMAND.COM, not in `system': an unquoted
`=' characters is treated as a delimiter by COMMAND.COM.  (Old
versions of COMMAND.COM, such as the one in DOS 5.0, don't support
quoting, so `=' is _always_ a delimiter there.)

(COMMAND.COM is in this example invoked by `system' because it doesn't
find a program called `Foo=bar', with or without an executable
extension.)