1 /*	$OpenBSD: perror.c,v 1.8 2005/08/08 08:05:36 espie Exp $ */
2 /*
3  * Copyright (c) 1988, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/uio.h>
33 #include <unistd.h>
34 #include <errno.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <limits.h>
38 
39 void
perror(const char * s)40 perror(const char *s)
41 {
42 	struct iovec *v;
43 	struct iovec iov[4];
44 	char buf[NL_TEXTMAX];
45 
46 	v = iov;
47 	if (s && *s) {
48 		v->iov_base = (char *)s;
49 		v->iov_len = strlen(s);
50 		v++;
51 		v->iov_base = ": ";
52 		v->iov_len = 2;
53 		v++;
54 	}
55 	(void)strerror_r(errno, buf, sizeof(buf));
56 	v->iov_base = buf;
57 	v->iov_len = strlen(v->iov_base);
58 	v++;
59 	v->iov_base = "\n";
60 	v->iov_len = 1;
61 	(void)writev(STDERR_FILENO, iov, (v - iov) + 1);
62 }
63