3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Guy Harris at Network Appliance Corp.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
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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
36 * @(#) Copyright (c) 1994 The Regents of the University of California. All rights reserved.
37 * @(#)random.c 8.5 (Berkeley) 4/5/94
38 * $FreeBSD: src/games/random/random.c,v 1.11.2.1 2003/02/15 10:34:35 seanc Exp $
39 * $DragonFly: src/games/random/random.c,v 1.2 2003/06/17 04:25:24 dillon Exp $
42 #include <sys/types.h>
54 #include "randomize_fd.h"
56 static void usage(void);
59 main(int argc, char *argv[])
62 int ch, fd, random_exit, randomize_lines, random_type, ret,
63 selected, unique_output, unbuffer_output;
68 random_type = RANDOM_TYPE_UNSET;
69 random_exit = randomize_lines = random_type = unbuffer_output = 0;
71 while ((ch = getopt(argc, argv, "ef:hlruUw")) != -1)
78 if (!strcmp(optarg, "-"))
79 filename = strdup("/dev/fd/0");
85 random_type = RANDOM_TYPE_LINES;
100 random_type = RANDOM_TYPE_WORDS;
113 denom = (randomize_lines ? 1 : 2);
117 denom = strtod(*argv, &ep);
120 if (denom <= 0 || *ep != '\0')
121 errx(1, "denominator is not valid.");
122 if (random_exit && denom > 255)
123 errx(1, "denominator must be <= 255 for random exit.");
133 * Act as a filter, randomly choosing lines of the standard input
134 * to write to the standard output.
137 setbuf(stdout, NULL);
140 * Act as a filter, randomizing lines read in from a given file
141 * descriptor and write the output to standard output.
143 if (randomize_lines) {
144 if ((fd = open(filename, O_RDONLY, 0)) < 0)
145 err(1, "%s", filename);
146 ret = randomize_fd(fd, random_type, unique_output, denom);
151 /* Compute a random exit status between 0 and denom - 1. */
153 return (int)((denom * random()) / LONG_MAX);
156 * Select whether to print the first line. (Prime the pump.)
157 * We find a random number between 0 and denom - 1 and, if it's
158 * 0 (which has a 1 / denom chance of being true), we select the
161 selected = (int)(denom * random() / LONG_MAX) == 0;
162 while ((ch = getchar()) != EOF) {
166 /* End of that line. See if we got an error. */
170 /* Now see if the next line is to be printed. */
171 selected = (int)(denom * random() / LONG_MAX) == 0;
183 fprintf(stderr, "usage: random [-elruUw] [-f filename] [denominator]\n");