Hi ! On Wed, Aug 25, 1999 at 02:24:45PM +1200, Mario Becroft wrote: > Firstly, I noticed today that the command "cat /dev/random" freezes the > machine. Did it really freeze the machine, or did it just stop giving output after some lines? > Otherwise maybe /dev/random would work if someone would explain how to > use it. /dev/random is used to produce cryptographically secure random numbers, i.e. there's no way to predict the current state, the next number returned, nor to reproduce a sequence based on a given state (you could use it for one-time-pads, for example). For this, the device monitors several sources of noise (keyboard input, mouse movement, context switches, etc., though I'm not sure what exactly the MiNT port monitors) to generate a "pool of entropy". If you read too often from that pool, its level of entropy will drop too low and /dev/random will block until it's grown enough to return strong random numbers again. If you just need "quite good" random numbers (which I guess as you considered using Random()), switch to using /dev/urandom. This one will never block, but return cryptographically weak random numbers once the pool's level of entropy has dropped so far that /dev/random would block. Note, though, that cryptographically strong random numbers are not necessarily suitable for things like simulating dice, because their primary purpose is to generate non-predictable/non-reproducable sequences of numbers, which may not match your expectation of "real word randomness". Ciao Thomas -- Thomas Binder (Gryf @ IRCNet) gryf@hrzpub.tu-darmstadt.de PGP-key available on request! binder@rbg.informatik.tu-darmstadt.de Vote against SPAM: http://www.politik-digital.de/spam/
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