Date: Thu, 16 Aug 2001 00:23:20 +0300
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: "Tim Van Holder" <tim DOT van DOT holder AT pandora DOT be>
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CC: djgpp-workers AT delorie DOT com
In-reply-to: <CAEGKOHJKAAFPKOCLHDIMELJCGAA.tim.van.holder@pandora.be>
Subject: Re: Very strange behaviour in our Perl port (redirection issue?)
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> From: "Tim Van Holder" <tim DOT van DOT holder AT pandora DOT be>
> Date: Wed, 15 Aug 2001 19:50:24 +0200
> 
> I ran m4 under gdb under Perl.  The fopen() succeeds and gives FD 4.

Handle 4?  That's preconnected to the printer, at least initially.
Does Perl or m4 close it at startup?  If not, I can't understand how
did m4 get handle 4 from fopen.

> How can Perl mess up FD's that are available to the child program?

Maybe Perl assumes that the handles are by default not inherited, or
calls the appropriate FCNTL function to make them not inherited.  We
don't support that, unless you build with the CVS library, where Mark
added that feature.  So in stock v2.03, all handles are inherited by
the child program, and thus point to the same files/devices that they
are inside Perl.