Path: utzoo!mnetor!uunet!husc6!mailrus!nrl-cmf!ames!pasteur!ucbvax!miro.Berkeley.EDU!ph
From: ph@miro.Berkeley.EDU (Paul Heckbert)
Newsgroups: comp.bugs.4bsd
Subject: csh arithmetic bug
Message-ID: <23570@ucbvax.BERKELEY.EDU>
Date: 10 Apr 88 19:22:50 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Reply-To: ph@miro.Berkeley.EDU (Paul Heckbert)
Organization: University of California, Berkeley
Lines: 16

Beware of doing arithmetic in csh, it's buggy!

The command	@ x = 0 - 1 + 2		sets x to -3	(should be 1)

The command	@ x = 0 - 1 - 2		sets x to 1	(should be -3)

(same error with Sun UNIX 3.5 on Sun3 and 4.3 BSD on Vax780)

csh must be parsing right-associatively by mistake!
Division has a similar problem.

It's hard to believe that a bug like this would persist for 8 years.

Paul Heckbert, CS grad student
508-7 Evans Hall, UC Berkeley		UUCP: ucbvax!miro.berkeley.edu!ph
Berkeley, CA 94720			ARPA: ph@miro.berkeley.edu