Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!lll-winken!uunet!ficc!peter
From: peter@ficc.uu.net (Peter da Silva)
Newsgroups: comp.unix.wizards
Subject: Re: friendly messages
Message-ID: <3621@ficc.uu.net>
Date: 30 Mar 89 15:41:16 GMT
References: <435@laic.UUCP> <955@auspex.UUCP> <9218@bloom-beacon.MIT.EDU> <1411@moscom.UUCP>
Organization: Xenix Support
Lines: 22

Neither of these solutions is correct:

In article <1411@moscom.UUCP>, jgp@moscom.UUCP (Jim Prescott) writes:
> 	fprintf(stderr, "%s: %s", Progname, buf);
> 	if (*(buf + strlen(buf) - 1) != '\n')
> 		perror("");

If this is the first time I/O is done, on at least some machines stdio
will call isatty(0) to determine if stdout should be unbuffered. It will
not save and restore errno. Your program may give such useful advice
as:

	foobar: can't open file barfoo -- Not a typewriter.

or:

	foobar: can't open file barfoo -- Inappropriate ioctl for device.
-- 
Peter da Silva, Xenix Support, Ferranti International Controls Corporation.

Business: uunet.uu.net!ficc!peter, peter@ficc.uu.net, +1 713 274 5180.
Personal: ...!texbell!sugar!peter, peter@sugar.hackercorp.com.