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From: "Tim Van Holder" <tim DOT van DOT holder AT pandora DOT be>
To: <djgpp-workers AT delorie DOT com>, <eliz AT is DOT elta DOT co DOT il>
Subject: Re: frlist.c proposed patch
Date: Fri, 11 Jan 2002 20:45:30 +0100
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> > You mean that ANSI/Posix might require that stdin/stdout/stderr be
> > always valid and ready to use?

I don't have the ANSI C standard.
ANSI C++ merely mentions them as part of cstdio (either as variable or
macro).
POSIX draft 6 lists them as parts of stdio.h; they're described as
objects associated with standard in/output.  Since the parent closed
those, I would suggest it's perfectly valid to have them be
"unwritable";  they're associated with a closed file, so errors are
acceptable.

A bigger problem is that several Unix-born programs assume handles 0, 1,
2 to be the standard streams (in the best case, they use STDOUT_FILENO
or similar macros, but it biols down to the same assumption).
To cater for that, we could just ensure fd's 0-4 are always opened
(so user-space fd's would be 5 and up), e.g. by opening NUL when one
of them is closed at startup.  Do we control the FD, or do we just
have to make do with what DOS gives us?