Article View: comp.std.c
Article #5565Re: volatile registers
From: Brian Matthews
Date: Fri, 06 Jan 1989 17:14
Date: Fri, 06 Jan 1989 17:14
32 lines
1369 bytes
1369 bytes
The Beach Bum (jfh@rpp386.Dallas.TX.US) writes:
|A common usage is in interrupt [ software ] handlers where the
|signal catching routine sets a flag and returns.
|
|The proper definition for such a flag should be
|
|in catch.c:
|--
|int sigflag;
|
|int catch (sig)
|{
| ...
| sigflag = 1;
| ...
|}
|--
|then outside catch.c you must use
|
|extern volatile int sigflag;
The spirit of the posting is correct, but there are a couple of technical
errors.
First, the type of sigflag should be sig_atomic_t, not int. Second, as
the function argument to signal is void (*fn)(int), catch should be a
void function. See the signal handling section of the draft (section
4.7, I believe).
--
Brian L. Matthews blm@cxsea.UUCP ...{mnetor,uw-beaver!ssc-vax}!cxsea!blm
+1 206 251 6811 Computer X Inc. - a division of Motorola New Enterprises
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Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!lll-winken!ames!mailrus!cornell!uw-beaver!ssc-vax!cxsea!blm From: blm@cxsea.UUCP (Brian Matthews) Newsgroups: comp.std.c Subject: Re: volatile registers Message-ID: <2592@cxsea.UUCP> Date: 6 Jan 89 17:14:38 GMT References: <141@bms-at.UUCP> <275@twwells.uucp> <15166@mimsy.UUCP> <9236@smoke.BRL.MIL> <15171@mimsy.UUCP> <9316@ihlpb.ATT.COM> <2337@cuux <10720@rpp386.Dallas.TX.US> Reply-To: blm@cxsea.UUCP (Brian Matthews) Organization: Computer X Inc. Lines: 32