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Mail Archives: djgpp-workers/2003/03/07/20:30:23

Date: Fri, 7 Mar 2003 20:30:22 -0500
Message-Id: <200303080130.h281UMb24534@envy.delorie.com>
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From: DJ Delorie <dj AT delorie DOT com>
To: djgpp-workers AT delorie DOT com
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In-reply-to: <3E69434C.B420FA9D@phekda.freeserve.co.uk> (message from Richard
Dawe on Sat, 08 Mar 2003 01:11:40 +0000)
Subject: Re: New POSIX: pwrite [PATCH]
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> I thought we were talking about how to detect TTYs that have been
> redirected (aka piped), so that we can fail pwrite and set errno ==
> ESPIPE.

> I see what you mean. Are all character devices TTYs? Or is that an
> oxymoronic question?

In unix there is a difference between a tty and other character
devices.  In dos, I'm not sure we can really tell - there isn't enough
information in the device bits to tell.  clock$ for example, probably
isn't a "tty" per se, but in all the contexts I can think of where it
makes sense to use isatty() in djgpp, clock$ is one of them.

In the case of redirected stdout, for example, we still can't tell the
difference between anything other than devices (stdout$, clock$, com1,
null, etc) and files (including pipes to other programs, which we
fake).

So while I think the question is meaningful, I also think it's moot.

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