Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!bionet!apple!rutgers!att!cbnewsl!mpl
From: mpl@cbnewsl.ATT.COM (michael.p.lindner)
Newsgroups: comp.lang.c
Subject: Re: comma operator
Summary: learn C, then post
Message-ID: <1351@cbnewsl.ATT.COM>
Date: 2 Aug 89 16:26:52 GMT
References: <10099@mpx2.mpx.com> <93@microsoft.UUCP> <10100@mpx2.mpx.com> <44c53d5b.f9df@gtephx.UUCP>
Organization: AT&T Bell Laboratories
Lines: 19

In article <... (names hidden to protect the guilty)
> > dandb@k.gp.cs.cmu.edu (Dean Rubine) writes:
> > >I also occasionally use the comma to save braces:
> > >	if((f = fopen(file, "r")) == NULL)
> > >		fprintf(stderr, "Can't open %s\n", file), exit(2);
> 
> various erroneous discussions of how order of evaluation is wrong
> or that these are statements and can't be used as expressions.

***FLAME ON!***
Sigh.  RTFM!  The comma operator guarantees left to right evaluation,
and fprintf(...) and exit(...) ARE valid expressions in C.
sputter sputter - flame off.

Mike Lindner
attunix!mpl or mpl@attunix.att.com
AT&T Bell Laboratories
190 River Rd.
Summit, NJ 07901