From:	loafman AT gte DOT net (Kenneth Loafman)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Volatile
Date:	7 Aug 1997 17:13:53 GMT
Organization:	Loafman Software
Lines:	23
Message-ID:	<5scvoh$iem$1@gte2.gte.net>
References:	<33E8495B DOT 3EBC AT starnets DOT ro> <33E8C02A DOT 438A AT sprintmail DOT com>
Reply-To:	loafman AT gte DOT net
NNTP-Posting-Host:	dfw73143.gte.net
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

On Wed, 06 Aug 1997 11:19:22 -0700, Ionicis <anfamily AT sprintmail DOT com>
wrote:

>Korenschi Francisc Eduard wrote:
>> 
>> Hi,
>> 
>>   I know it sounds crazy, but what does the 'voltaile' with a
>> variable/function ?
>> 
>>    Thanx for bothering,
>>   Eduard
>The volatile keyword makes a variable not "changable" by anything except
>the code itself.  I'm pretty sure that's what it means  :)

Just the opposite.  Volatile means that the variable MAY BE changed by
something other then the code itself, i.e. by a device, by an interrupt
service routine, by another process.  What this means to the compiler is
that it should not cache this variable in a register since each reference
to it should come from the volatile memory location.

...Kenneth

- Raw text -