strcspn(3) complexity improvement

[Andre Guibert de Bruet]

On Thu, 31 Mar 2005, Peter Jeremy wrote:

> On Wed, 2005-Mar-30 10:31:45 -0800, Brooks Davis wrote:
>> The real question I have is, how long does the string need to be before
>> this is a win and how much does it hurt for typical string lengths?
>> I've written code with strcspn that needed to perform well, but it was
>> parsing 80-column punch card derived formats.
>
> I was thinking about this last night.  The easy way is to generate random
> "string" and "charset" arrays of varying length and time both strcspn()
> variants - this gives you two two-dimensional surfaces showing timing
> vs argument size.  The difficulty is visualising the result and
> deciding whether pairs of random strings are realistic.

I would be tempted to use list traffic as the haystack and random words of 
differing lengths from the aspell dict for the needle.

Andy

| Andre Guibert de Bruet | Enterprise Software Consultant >
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