summaryrefslogtreecommitdiff
path: root/src/lib/libc/stdlib/rand.3
diff options
context:
space:
mode:
Diffstat (limited to 'src/lib/libc/stdlib/rand.3')
-rw-r--r--src/lib/libc/stdlib/rand.3102
1 files changed, 102 insertions, 0 deletions
diff --git a/src/lib/libc/stdlib/rand.3 b/src/lib/libc/stdlib/rand.3
new file mode 100644
index 0000000000..8899c2e104
--- /dev/null
+++ b/src/lib/libc/stdlib/rand.3
@@ -0,0 +1,102 @@
1.\" Copyright (c) 1990, 1991 The Regents of the University of California.
2.\" All rights reserved.
3.\"
4.\" This code is derived from software contributed to Berkeley by
5.\" the American National Standards Committee X3, on Information
6.\" Processing Systems.
7.\"
8.\" Redistribution and use in source and binary forms, with or without
9.\" modification, are permitted provided that the following conditions
10.\" are met:
11.\" 1. Redistributions of source code must retain the above copyright
12.\" notice, this list of conditions and the following disclaimer.
13.\" 2. Redistributions in binary form must reproduce the above copyright
14.\" notice, this list of conditions and the following disclaimer in the
15.\" documentation and/or other materials provided with the distribution.
16.\" 3. All advertising materials mentioning features or use of this software
17.\" must display the following acknowledgement:
18.\" This product includes software developed by the University of
19.\" California, Berkeley and its contributors.
20.\" 4. Neither the name of the University nor the names of its contributors
21.\" may be used to endorse or promote products derived from this software
22.\" without specific prior written permission.
23.\"
24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34.\" SUCH DAMAGE.
35.\"
36.\" $OpenBSD: rand.3,v 1.8 2001/05/13 23:38:02 millert Exp $
37.\"
38.Dd June 29, 1991
39.Dt RAND 3
40.Os
41.Sh NAME
42.Nm rand ,
43.Nm srand
44.Nd bad random number generator
45.Sh SYNOPSIS
46.Fd #include <stdlib.h>
47.Ft void
48.Fn srand "unsigned int seed"
49.Ft int
50.Fn rand void
51.Ft int
52.Fn rand_r "unsigned int *seed"
53.Sh DESCRIPTION
54.Bf -symbolic
55These interfaces are obsoleted by
56.Xr random 3 .
57.Ef
58.Pp
59The
60.Fn rand
61function computes a sequence of pseudo-random integers in the range
62of 0 to
63.Dv RAND_MAX
64(as defined by the header file
65.Aq Pa stdlib.h ) .
66.Pp
67The
68.Fn srand
69function sets its argument as the seed for a new sequence of
70pseudo-random numbers to be returned by
71.Fn rand .
72These sequences are repeatable by calling
73.Fn srand
74with the same seed value.
75.Pp
76If no seed value is provided, the functions are automatically
77seeded with a value of 1.
78.Pp
79The
80.Fn rand_r
81is a thread-safe version of
82.Fn rand .
83Storage for the seed must be provided through the
84.Fa seed
85argument, and needs to have been initialized by the caller.
86.Sh SEE ALSO
87.Xr arc4random 3 ,
88.Xr rand48 3 ,
89.Xr random 3
90.Sh STANDARDS
91The
92.Fn rand
93and
94.Fn srand
95functions conform to
96.St -ansiC .
97.Pp
98The
99.Fn rand_r
100function conforms to ISO/IEC 9945-1 ANSI/IEEE
101.Pq Dq Tn POSIX
102Std 1003.1c Draft 10.