[erlang-questions] checksum calculation

[jm]

Gamoto wrote:
> Richard,
> Suppose you have an industrial machine which send messages following by the checksum calculated by the xor of all bytes, what can I do with your advices ;-)
> John
>   
I take it by this that this is a given and out of your control. In which 
case your stuck, but should politely tell the manufacture they're a 
bunch of idiots highlighting the drawbacks mentioned by Richard and try 
to get the next revision fixed.

If your lucky enough to be able change the checksum take a look at

adler32/1 in the kernel/erlang section of the manual, or
crc32/1    in the same section.

example use of both,

 > erlang:adler32([1,2,3,[4,5]]).
2621456

 > erlang:crc32([1,2,3,[4,5]]). 
1191942644

I hope this solves your problem.

Jeff.