Function becomes useful when we need hex value of crc32() result, even if it is negative.
Python, 15 lines
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import binascii def crc2hex(crc): res='' for i in range(4): t=crc & 0xFF crc >>= 8 res='%02X%s' % (t, res) return res if __name__=='__main__': test='hello world! and Python too ;)' crc=binascii.crc32(test) print 'CRC:', crc print 'CRC in hex:', crc2hex(crc)
A special formatting function is not needed. You can easily convert a 32 bit numeric value into an 8 byte hex string without writting a special function to do it by just using string objects' built-in %operator.
Note the final line in the following:
even if is it negative? i don't think so
You could use the following statement:
'%08X' % (binascii.crc32(test) & 0xffffffff)
Yes, it works. However, I prefer to use well-debugged function instead of using nuts-and-bolts in print statement. Thank you!
This works great.
However the million dollar question: If I use:
How do I convert
'some random string'?
Hi Michael, it is impossible to restore source string from CRC32, you only can brute force strings which have the same CRC32 value ;).
See also: http://en.wikipedia.org/wiki/Hash_function#Non-invertible