pseudo-random number generator.

unsigned long int next = 1;

/*rand: return pseudo-random integer on 0...32767 */
int rand(void)
{
   next = next * 1103515245  + 12345;
   return (unsigned int )(next/65536) % 32768;
}

/*srand; set seed for rand() */
void srand(unsigned int seed)
{
    next = seed;
}