Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!brl-adm!brl-sem!ron From: ron@brl-sem.ARPA (Ron Natalie) Newsgroups: comp.lang.c Subject: Re: is it really necessary for character values to be positive? Message-ID: <548@brl-sem.ARPA> Date: Tue, 30-Dec-86 13:12:38 EST Article-I.D.: brl-sem.548 Posted: Tue Dec 30 13:12:38 1986 Date-Received: Tue, 30-Dec-86 21:39:10 EST References: <39@houligan.UUCP> <289@haddock.UUCP> Organization: Electronic Brain Research Lab Lines: 13 In article <289@haddock.UUCP>, karl@haddock.UUCP (Karl Heuer) writes: > In article <39@houligan.UUCP> dave@murphy.UUCP writes: > >Summary: invent an 8-bit character set and then let some of them be negative > > Suppose I am using such a system, and one of the characters -- call it '@' -- > has a negative value. The following program will not work: > main() { int c; ... c = getchar(); ... if (c == '@') ... } Getchar returns int. The int has a character in it. Before trying to use it as such, you ought to either place it back into a character variable explicitly or use a cast to char... main() { int c; ... c = getchar(); ... if ((char) c == '@') ... }