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2002 Jan 18 08:58

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Re: [vox-tech] C question: global vs local const
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Re: [vox-tech] C question: global vs local const

Keywords: global, local, c, variables, const

On Fri, 18 Jan 2002, Peter Jay Salzman wrote:

> does this apply to static variables too?  i have a situation where a
> function is called many times over:
> void function( ..., long double dr)
> {
> 	long double variable = expensive_calculation * dr;
> 	...
> }
> i'd like to declare variable as static, since both expensive_calculation
> and dr remain constant through the entire program.  i can't declare dr
> as being global because it depends on other parameters that need to be
> calculated at run time (but otherwise don't change).

Hmmm... ummm... hmmm...  Think, think...

Yes.  If they aren't calculated at compile time, then you need some way to
tell whether a function call during runtime is the "first call".  This
would have to be something like:

   int function(int arg)
         /* initialize static variables */

      blah blah...

This adds hidden overhead to a function call, which would be a no-no for C.

-Mark (making it up as he goes...)

Mark K. Kim
PGP key available upon request.

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