Thus spake Paul Herman <[EMAIL PROTECTED]>: > On Wed, 19 Feb 2003 [EMAIL PROTECTED] wrote: > > > In message <[EMAIL PROTECTED]>, Paul Herma > > n writes: > > > > > arc4random() returns random numbers in the range of 0 to > > > (2**32)-1, and therefore has twice the range of RAND_MAX. > > > > Good. > > > > > EXAMPLES > > > The following produces a drop-in replacement for the traditional > > > random() and rand() functions using arc4random(): > > > #define arc4random31() (arc4random() & 0x7FFFFFFF) > > > > Not good. Only true on 32 bit archs. > > Heh? > > random(3) produces numbers between 0 and RAND_MAX on my alpha. > random(3) produces numbers between 0 and RAND_MAX on my i386. > (arc4random() & 0x7FFFFFFF) produces numbers between 0 and RAND_MAX on my alpha. > (arc4random() & 0x7FFFFFFF) produces numbers between 0 and RAND_MAX on my i386.
Your code should work fine, although it assumes RAND_MAX is 2^31-1, rather than using the symbolic constant. But I think if people were really interested in using arc4random() as a drop-in replacement for random(), they would have already written a libc function to mimic random(). Just documenting the range of arc4random() should be sufficient. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
