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Difference between cksum and sum in unix

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# 1  
Old 04-12-2010
Difference between cksum and sum in unix
i get 2 different values when i give cksum and sum command. Are they 2 different algorithms? can someone explain how this is different
# 2  
Old 04-12-2010
Please have a look at the starting lines of man pages for the both.
you will find clear explanation there.

like,

Code:
     cksum uses a portable algorithm based on a 32-bit Cyclic Redundancy
      Check.  This algorithm finds a broader spectrum of errors than the
      16-bit algorithms used by sum (see sum(1)).  The CRC is the sum of the
      following expressions, where x is each byte of the file.
 
           x^32 + x^26 + x^23 +x^22 + x^16 + x^12 + x^11 + x^10 + x^8 + x^7
           + x^5 + x^4 + x^2 + x^1 + x^0

# 3  
Old 04-12-2010
The algorithms are quite different.
sum just adds up the binary equivalent of the bytes.
chsum is a proper CRC check.

sum will not spot byte reversal or even lines swapped over. cksum will.
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