On Apr 15, 12:56 pm, Nigel Rantor <wig...@wiggly.org> wrote: > Adam Olsen wrote: > > The chance of *accidentally* producing a collision, although > > technically possible, is so extraordinarily rare that it's completely > > overshadowed by the risk of a hardware or software failure producing > > an incorrect result. > > Not when you're using them to compare lots of files. > > Trust me. Been there, done that, got the t-shirt. > > Using hash functions to tell whether or not files are identical is an > error waiting to happen. > > But please, do so if it makes you feel happy, you'll just eventually get > an incorrect result and not know it.
Please tell us what hash you used and provide the two files that collided. If your hash is 256 bits, then you need around 2**128 files to produce a collision. This is known as a Birthday Attack. I seriously doubt you had that many files, which suggests something else went wrong. -- http://mail.python.org/mailman/listinfo/python-list