Subject: Re: RFC: memmem(3)
To: None <>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-userlevel
Date: 03/02/2003 14:45:28
>> + searching is usually much faster
> That was my first thought too - if something needs this, it would
> probably better use some more clever algorithm, like Rabin/Karp or
> Knuth/Morris/Pratt (with similar interface changes as you describe).

I'm not sure which algorithm I'm using in terms of names like those.
The name Boyer/Moore comes to mind, but I'm not sure exactly what that
is so I could be misled there.

Here's the interface I'm using:

        searchstr_maketbl(unsigned char (*table)[256],
           const unsigned char *string, unsigned int len,
           const unsigned char equiv[256]);

        searchstr(const unsigned char *string, unsigned int stringlen,
           unsigned char (*table)[256], unsigned int tablelen);

The first function is the overhead call I referred to; the second
actually does the search.  The interface is not very general (in terms
of the underlying algorithm) because I wanted to avoid making the
library routines allocate memory.

Hm, the table argument to searchstr really ought to be
const unsigned char (*)[256].  And of course 256 should be something
more like UCHAR_MAX....

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