Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!wugate!uunet!bywater!arnor!uri
From: uri@arnor.UUCP (Uri Blumenthal)
Newsgroups: comp.lang.c
Subject: Re: ttyname() - question
Message-ID: <388@arnor.UUCP>
Date: 31 Aug 89 18:39:19 GMT
References: <192700003@hobbiton>
Organization: IBM Corp., Yorktown NY
Lines: 50

From article <192700003@hobbiton>, by fieland@hobbiton.prime.com:
> 
> tried this out on another Sun without the windows up.
> 
> Sure enough, the call in Main got the ttyname and the
> call in test didn't.
> 
> Clearly, results are system dependent.
> So how about it??? Any answers out there??????

This definitely works correctly (AIX system):
-------------------
#include <stdio.h>
void test()
{
	char *ttyname();

	printf("test: %s\n", ttyname(2));

}

main()
{
	char *ttyname();

	printf("main: %s\n", ttyname(2));
	test();

	exit(0);

}
-------------------------------

Points to be made:
	
	a) %s in 'printf' statement;

	b) the manual says:

		char *ttyname(fildes)
		int  fildes;

	   and when you call 'ttyname' WITHOUT proper parameter -
	   it does work from 'main', but doesn't work in subroutines.
	   Why? Implementation details, who cares?

Regards,
Uri.
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