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From: david@wubios.wustl.edu (David J. Camp)
Newsgroups: comp.unix.questions,comp.unix.xenix
Subject: Re: How to determine file being redirected to in C
Keywords: redirection
Message-ID: <325@wubios.wustl.edu>
Date: 3 Mar 89 21:24:50 GMT
References: <10@sherpa.UUCP> <7419@pyr.gatech.EDU>
Reply-To: david@wubios.UUCP (David J. Camp)
Distribution: na
Organization: Washington University (St. Louis)
Lines: 23

In article <7419@pyr.gatech.EDU> curci@stat.fsu.edu (Ray Curci (scri)) writes:
:>In article <10@sherpa.UUCP> rac@sherpa.UUCP (Roger A. Cornelius) writes:
:>>...  Anyway, can someone tell me how to determine (in C)
:>>if output is being redirected, or more precisely, how to determine the
:>>file output is being redirected to.  
:>>Roger      rac@sherpa
:>>           uunet!sherpa!rac
:>
:>You may want to investigate the isatty() function call.  I believe that
:>you can use something like:  isatty(stdout)  which will tell you if
:>standard out is going to a terminal (the usual case), or if it has been
:>redirected via a pipe or into a file.
:>
:>ray curci

I just received umpteen replies about this.  The function call is
isatty(fileno(stdout));
-David-
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