rev.c revision 1.5 
1/*	$NetBSD: rev.c,v 1.5 1995/09/28 08:49:40 tls Exp $	*/
2
3/*-
4 * Copyright (c) 1987, 1992, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#ifndef lint
37static char copyright[] =
38"@(#) Copyright (c) 1987, 1992, 1993\n\
39	The Regents of the University of California.  All rights reserved.\n";
40#endif /* not lint */
41
42#ifndef lint
43#if 0
44static char sccsid[] = "@(#)rev.c	8.3 (Berkeley) 5/4/95";
45#else
46static char rcsid[] = "$NetBSD: rev.c,v 1.5 1995/09/28 08:49:40 tls Exp $";
47#endif
48#endif /* not lint */
49
50#include <sys/types.h>
51
52#include <err.h>
53#include <errno.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58
59void usage __P((void));
60
61int
62main(argc, argv)
63	int argc;
64	char *argv[];
65{
66	register char *filename, *p, *t;
67	FILE *fp;
68	size_t len;
69	int ch, rval;
70
71	while ((ch = getopt(argc, argv, "")) != EOF)
72		switch(ch) {
73		case '?':
74		default:
75			usage();
76		}
77
78	argc -= optind;
79	argv += optind;
80
81	fp = stdin;
82	filename = "stdin";
83	rval = 0;
84	do {
85		if (*argv) {
86			if ((fp = fopen(*argv, "r")) == NULL) {
87				warn("%s", *argv);
88				rval = 1;
89				++argv;
90				continue;
91			}
92			filename = *argv++;
93		}
94		while ((p = fgetln(fp, &len)) != NULL) {
95			if (p[len - 1] == '\n')
96				--len;
97			t = p + len - 1;
98			for (t = p + len - 1; t >= p; --t)
99				putchar(*t);
100			putchar('\n');
101		}
102		if (ferror(fp)) {
103			warn("%s", filename);
104			rval = 1;
105		}
106		(void)fclose(fp);
107	} while(*argv);
108	exit(rval);
109}
110
111void
112usage()
113{
114	(void)fprintf(stderr, "usage: rev [file ...]\n");
115	exit(1);
116}
117