eprintf.c revision 1.1 1 /* $NetBSD: eprintf.c,v 1.1 1996/01/07 21:50:49 leo Exp $ */
2
3 /*
4 * Copyright (c) 1995 Waldi Ravens.
5 * 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 Waldi Ravens.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <fcntl.h>
34 #include <errno.h>
35 #include <stdio.h>
36 #include <stdarg.h>
37 #include <unistd.h>
38 #include "libtos.h"
39
40 static int output_redirected = 0;
41
42 void
43 redirect_output(fn)
44 char *fn;
45 {
46 int fd;
47
48 fd = creat(fn, 0666);
49 if (fd < 0 || dup2(fd, STDOUT_FILENO) < 0)
50 fatal(errno, "%s", fn);
51 output_redirected = 1;
52 }
53
54 /*
55 * Print output to stderr. When output is redirected,
56 * also write it to stdout.
57 */
58 int
59 eprintf(frm)
60 char *frm;
61 {
62 va_list args;
63 int rv;
64
65 va_start(args, frm);
66 rv = veprintf(frm, args);
67 va_end(args);
68 return(rv);
69 }
70
71 int
72 veprintf(frm, args)
73 char *frm;
74 va_list args;
75 {
76 int rv;
77
78 rv = vfprintf(stderr, frm, args);
79 if (output_redirected)
80 vfprintf(stdout, frm, args);
81 return(rv);
82 }
83