freebsd-src/lib/libc/stdlib/rand.3

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1994-05-27 06:00:24 +01:00
.\" Copyright (c) 1990, 1991, 1993
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.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
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.\" @(#)rand.3 8.1 (Berkeley) 6/4/93
.\"
.Dd June 4, 1993
.Dt RAND 3
.Os
.Sh NAME
.Nm rand ,
.Nm srand
.Nd bad random number generator
.Sh SYNOPSIS
.Fd #include <stdlib.h>
.Ft void
.Fn srand "unsigned seed"
.Ft int
.Fn rand void
.Sh DESCRIPTION
.Bf -symbolic
These interfaces are obsoleted by random(3).
.Ef
.Pp
The
.Fn rand
function computes a sequence of pseudo-random integers in the range
of 0 to
.Dv RAND_MAX
(as defined by the header file
.Aq Pa stdlib.h ) .
.Pp
The
.Fn srand
function sets its argument as the seed for a new sequence of
pseudo-random numbers to be returned by
.Fn rand .
These sequences are repeatable by calling
.Fn srand
with the same seed value.
.Pp
If no seed value is provided, the functions are automatically
seeded with a value of 1.
.Sh SEE ALSO
.Xr random 3
.Sh STANDARDS
The
.Fn rand
and
.Fn srand
functions
conform to
.St -ansiC .