To:	Eric Backus <ericb AT lsid DOT hp DOT com>
Cc:	djgpp AT sun DOT soe DOT clarkson DOT edu
Subject:	Re: stdin, stdout and friends, was: fstat() yet again
Date:	Sun, 29 May 94 14:12:59 +0300
From:	eliz AT is DOT elta DOT co DOT il

Eric Backus wrote:

> Keeping track is fine for files opened by the program, but you can't
> do that for stdin, stdout, and stderr.  All you have for those is a
> file handle...

As an aside on the standard files: I recently ported Diffutils to DJGPP and
were bugged by the following problem.  When DIFF discovers that a file is
BINARY, it must (under DOS) reopen it in BINARY mode, otherwise read() will
stop at the first ^Z character, and the files have a high probability of being
falsely declared identical (in fact, the version of DIFF distributed with
DJGPP has exactly this bug).  Now, if DIFF reads from stdin (which might be a
pipe or a redirected file), I couldn't find a way to change the file's reading
mode, so this was a lossage in my case: couldn't correctly handle binary files
if one of them comes via stdin.
My question is: is there ANY way to change open mode (TEXT vs BINARY) of the
stdin stream WITHOUT reopening it (which we obviously cannot do, as indicated
by Eric Backus)?  I think there is no PORTABLE (i.e. ANSI) way, but maybe
something DOS-specific or DJGPP-specific?

	Eli Zaretskii

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