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RAND(3V)                                                              RAND(3V)



NAME
       rand, srand - simple random number generator

SYNOPSIS
       srand(seed)
       int seed;

       rand()

DESCRIPTION
       rand()  uses a multiplicative congruential random number generator with
       period 2**32 to return successive pseudo-random numbers  in  the  range
       from 0 to (2**31)-1.

       srand()  can be called at any time to reset the random-number generator
       to a random starting point.  The generator is initially seeded  with  a
       value of 1.

SYSTEM V DESCRIPTION
       rand()  returns successive pseudo-random numbers in the range from 0 to
       (2**15)-1.

SEE ALSO
       drand48(3), random(3)

NOTES
       The spectral properties of rand() leave a great  deal  to  be  desired.
       drand48(3)  and  random(3)  provide much better, though more elaborate,
       random-number generators.

BUGS
       The low bits of the numbers generated are not very random; use the mid-
       dle bits.  In particular the lowest bit alternates between 0 and 1.



                                6 October 1989                        RAND(3V)