bsd man page for srand

RAND(3C)																  RAND(3C)

NAME
       rand, srand - random number generator

SYNOPSIS
       srand(seed)
       int seed;

       rand()

DESCRIPTION
       The newer random(3) should be used in new applications; rand remains for compatibilty.

       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 on the VAX, and (2**15)-1 on the PDP-11.

       The generator is reinitialized by calling srand with 1 as argument.  It can be set to a random starting point by calling srand  with  what-
       ever you like as argument.

SEE ALSO
       random(3)

7th Edition							September 29, 1985							  RAND(3C)