Xref: utzoo comp.lang.c:27303 comp.sys.ibm.pc.programmer:622
Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!pt.cs.cmu.edu!b.gp.cs.cmu.edu!ralf
From: ralf@b.gp.cs.cmu.edu (Ralf Brown)
Newsgroups: comp.lang.c,comp.sys.ibm.pc.programmer
Subject: Re: How to tell if stdin/stdout is redirected?
Message-ID: <8647@pt.cs.cmu.edu>
Date: 28 Mar 90 21:49:25 GMT
References: <807@tsdiag.ccur.com>
Organization: Carnegie-Mellon University, CS/RI
Lines: 18

In article <807@tsdiag.ccur.com> jeffs@tsdiag.ccur.com (Jeff Schnell) writes:
}I would like to know if there is a way to tell if stdin/stdout
}is redirected.  I would like it in Turbo C and/or Microsoft C
}and also in unix.

	isatty(fileno(stdin))

works for me under Turbo C (returns nonzero iff stdin points at a character 
device such as CON, PRN, etc) and should work under Unix (since that is where
isatty originated).



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