random

Generates pseudorandom numbers in a more random sequence.

Format 

#include  <stdlib.h>

long int random  (void);

Description

This function is a random number generator that has virtually the same calling sequence and initialization properties as the rand function, but produces sequences that are more random. The low 12 bits generated by rand go through a cyclic pattern. All bits generated by random are usable. For example, random() &1 produces a random binary value.

The random function uses a nonlinear additive feedback random number generator employing a default state array size of 31 integers to return successive pseudorandom numbers in the range from 0 to ( 231 )-1. The period of this random number generator is approximately 16*(( 231 )-1). The size of the state array determines the period of the random number generator. Increasing the state array size increases the period.

With a full 256 bytes of state information, the period of the random number generator is greater than 269 , and is sufficient for most purposes.

Like the rand function, the random function produces by default a sequence of numbers that you can duplicate by calling the srandom function with a value of 1 as the seed. The srandom function, unlike the srand function, does not return the old seed because the amount of state information used is more than a single word.

See also rand, srand, and srandom in this section.

Return Values
n  A random number. 

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