Path: chuka.playstation.co.uk!news
From: "pal" <palpalpalpal@<NO SPAM>hotmail.com>
Newsgroups: scee.yaroze.beginners
Subject: static variables
Date: 31 Oct 1999 23:57:47 GMT
Organization: PlayStation Net Yaroze (SCEE)
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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