xref: /netbsd-src/lib/libc/stdlib/rand.3 (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
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36.\"     from: @(#)rand.3	6.7 (Berkeley) 6/29/91
37.\"	$Id: rand.3,v 1.2 1993/08/01 07:44:20 mycroft Exp $
38.\"
39.Dd June 29, 1991
40.Dt RAND 3
41.Os
42.Sh NAME
43.Nm rand ,
44.Nm srand
45.Nd bad random number generator
46.Sh SYNOPSIS
47.Fd #include <stdlib.h>
48.Ft void
49.Fn srand "unsigned seed"
50.Ft int
51.Fn rand void
52.Sh DESCRIPTION
53.Bf -symbolic
54These interfaces are obsoleted by random(3).
55.Ef
56.Pp
57The
58.Fn rand
59function computes a sequence of pseudo-random integers in the range
60of 0 to
61.Dv RAND_MAX
62(as defined by the header file
63.Aq Pa stdlib.h ) .
64.Pp
65The
66.Fn srand
67function sets its argument as the seed for a new sequence of
68pseudo-random numbers to be returned by
69.Fn rand .
70These sequences are repeatable by calling
71.Fn srand
72with the same seed value.
73.Pp
74If no seed value is provided, the functions are automatically
75seeded with a value of 1.
76.Sh SEE ALSO
77.Xr random 3
78.Sh STANDARDS
79The
80.Fn rand
81and
82.Fn srand
83functions
84conform to
85.St -ansiC .
86