Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!husc6!rice!uw-beaver!cornell!rochester!pt.cs.cmu.edu!MARCOZ.BOLTZ.CS.CMU.EDU!marcoz
From: marcoz@MARCOZ.BOLTZ.CS.CMU.EDU (Marco Zagha)
Newsgroups: comp.lang.c
Subject: Re: getting users' tty # into a C program
Summary: popen returns a FILE pointer not a descriptor
Message-ID: <4418@pt.cs.cmu.edu>
Date: 6 Mar 89 13:50:01 GMT
References: <441@lakesys.UUCP> <9794@smoke.BRL.MIL> <52746@yale-celray.yale.UUCP>
Organization: Carnegie-Mellon University, CS/RI
Lines: 15

In article 52746@yale-celray.yale.UUCP> spolsky-joel@CS.YALE.EDU (Joel Spolsky) writes:

> failing that try fd=popen("tty"); fscanf(fd,"%s",ttyname); close(fd)

popen returns a FILE pointer.  To close this file pointer use pclose(),
not close(). I think this is what should be done (as you said, 
failing ttyname()):

FILE *f;
f=popen("/usr/bin/tty","r"); fscanf(f,"%s",ttyname); pclose(f)

== Marco (marcoz@cs.cmu.edu)



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