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binascii.crc32 results not matching

Raymond L. Buvel levub137 at wi.rr.com
Sat Dec 10 15:03:44 EST 2005 
Larry Bates wrote:
<snip a lot of code>

Looking over the code, it seems very inefficient and hard to understand.
 You really should check out the following.

http://sourceforge.net/projects/crcmod/

It will allow you to generate efficient CRC functions for use in Python
and in C or C++.  The only thing you need to input is the polynomial,
the bit ordering, and the starting value.  The unit test gives a number
of polynomials including the one you are using which is:

polynomial: 0x104C11DB7, bit reverse algorithm

If you are just looking for a utility on Linux to do nightly checking of
files, I strongly recommend md5sum.  My timing tests indicate that the
MD5 algorithm is comparable or slightly faster than a 32-bit CRC and
certainly faster than the code you are trying to port.  It also has the
advantage of being a standard Linux command so you don't need to code
anything.

Ray
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