xref: /netbsd-src/lib/libc/stdlib/rand.3 (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1.\"	$NetBSD: rand.3,v 1.3 1995/12/28 08:52:39 thorpej Exp $
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38.\"     from: @(#)rand.3	6.7 (Berkeley) 6/29/91
39.\"
40.Dd June 29, 1991
41.Dt RAND 3
42.Os
43.Sh NAME
44.Nm rand ,
45.Nm srand
46.Nd bad random number generator
47.Sh SYNOPSIS
48.Fd #include <stdlib.h>
49.Ft void
50.Fn srand "unsigned seed"
51.Ft int
52.Fn rand void
53.Sh DESCRIPTION
54.Bf -symbolic
55These interfaces are obsoleted by random(3).
56.Ef
57.Pp
58The
59.Fn rand
60function computes a sequence of pseudo-random integers in the range
61of 0 to
62.Dv RAND_MAX
63(as defined by the header file
64.Aq Pa stdlib.h ) .
65.Pp
66The
67.Fn srand
68function sets its argument as the seed for a new sequence of
69pseudo-random numbers to be returned by
70.Fn rand .
71These sequences are repeatable by calling
72.Fn srand
73with the same seed value.
74.Pp
75If no seed value is provided, the functions are automatically
76seeded with a value of 1.
77.Sh SEE ALSO
78.Xr random 3
79.Sh STANDARDS
80The
81.Fn rand
82and
83.Fn srand
84functions
85conform to
86.St -ansiC .
87