Path: chuka.playstation.co.uk!news
From: sosman@terratron.com (Steven Osman)
Newsgroups: scee.yaroze.beginners
Subject: Re: static variables
Date: Mon, 01 Nov 1999 02:55:17 GMT
Organization: PlayStation Net Yaroze (SCEE)
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References: <7vhr5g$4g31@chuka.playstation.co.uk> <7vi161$a6n2@chuka.playstation.co.uk> <01bf23f9$82197ac0$429124c3@pal-s-omnibook>
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Also, and quite importantly... local variables are allocated as the
function is called.  That means, when you are not in the function, the
memory is not taken up!

If you have a non-recursive application, you can't just make
everything static for speed, without considering that you will be
consuming a lot of memory, given enough variables.

Steven


On 31 Oct 1999 23:57:47 GMT, "pal" <palpalpalpal@<NO SPAM>hotmail.com>
wrote:

>Nathan Miller wrote :
><snip>
>>I've recently been reading about using 'static' variables to 'move
>>them off the stack' but I'm lost as to what it means.
><snip>
>
>Variables declared in a function body are allocated on the stack when the
>function is entered, unless you specify otherwise. If you wish so, you can
>force them to go in registers ("register" modifier) for faster access, or
>to be global ("static" modifier) so that they're allocated once only before
>the program starts.
>
>When a variable is declared "static", it behaves exactly as if it were
>declared outside the function (scope aside). There's no more need for
>allocating it on the stack every time the function is entered - so
>execution time is gained. Be aware however that the function must not be
>called again before it ends (well, technically it can, but you must manage
>to avoid it corrupting its static variables) - that means, no recursion and
>no parallelism. Be careful with initialisation too.
>
>
>
>pal