NAME

rand, srand − simple random-number generator

SYNOPSIS

int rand ( )

void srand (seed)
unsigned seed;

DESCRIPTION

Rand uses a multiplicative congruential random-number generator with period 232 that returns successive pseudo-random numbers in the range from 0 to 215−1. 

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. 

NOTE

The spectral properties of rand leave a great deal to be desired.  Drand48(3C) provides a much better, though more elaborate, random-number generator.

SEE ALSO

drand48(3C). 

STANDARDS CONFORMANCE

rand: SVID2, XPG2, XPG3, POSIX.1, FIPS 151-1, ANSI C

srand: SVID2, XPG2, XPG3, POSIX.1, FIPS 151-1, ANSI C

Hewlett-Packard Company  —  HP-UX Release 7.0: Sept 1989