Path: utzoo!mnetor!uunet!husc6!necntc!ima!haddock!karl
From: karl@haddock.ISC.COM (Karl Heuer)
Newsgroups: comp.lang.c
Subject: Re: volatile
Message-ID: <3237@haddock.ISC.COM>
Date: 30 Mar 88 18:16:49 GMT
References: <12578@brl-adm.ARPA> <1988Mar25.172355.348@utzoo.uucp> <588@imagine.PAWL.RPI.EDU> <1988Mar29.004454.2867@utzoo.uucp> <134@wyse.wyse.com>
Reply-To: karl@haddock.ima.isc.com (Karl Heuer)
Organization: Interactive Systems, Boston
Lines: 21

In article <134@wyse.wyse.com> mikew@wyse.UUCP (Mike Wexler) writes:
>In article <1988Mar29.004454.2867@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes:
>>the sort of code we're talking about isn't portable anyway.
>I would disagree that is isn't possible to write portable code that requires
>volatiles. An example(possibly the only one), is the use of System V
>or Berkeley shared memory.

Why drag shared memory into it?  Isn't the following an example of a strictly
conforming program that needs volatile?

#include <signal.h>
static sig_atomic_t volatile gotcha;
static void catch(int signo) { gotcha = 1; }
int main(void) {
    (void)signal(SIGINT, catch);
    gotcha = 0;
    do; while (!gotcha);
    return (0);
}

Karl W. Z. Heuer (ima!haddock!karl or karl@haddock.isc.com), The Walking Lint