xref: /freebsd/usr.bin/nice/nice.c (revision ee2ea5ceafed78a5bd9810beb9e3ca927180c226)
1 /*
2  * Copyright (c) 1989, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1989, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #if 0
41 #ifndef lint
42 static char sccsid[] = "@(#)nice.c	8.2 (Berkeley) 4/16/94";
43 #endif /* not lint */
44 #endif
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <sys/types.h>
50 #include <sys/time.h>
51 #include <sys/resource.h>
52 
53 #include <ctype.h>
54 #include <err.h>
55 #include <errno.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <unistd.h>
59 #include <string.h>
60 
61 #define	DEFNICE	10
62 
63 void usage(void);
64 
65 int
66 main(argc, argv)
67 	int argc;
68 	char *argv[];
69 {
70 	int niceness = DEFNICE;
71 
72 	if (argc < 2)
73 		usage();
74 
75 	if (argv[1][0] == '-') {
76 		if (argv[1][1] == '-' || isdigit(argv[1][1])) {
77 			niceness = atoi(argv[1] + 1);
78 			++argv;
79 		} else
80 			errx(1, "illegal option -- %s", argv[1]);
81 	}
82 
83 	if (argv[1] == NULL)
84 		usage();
85 
86 	errno = 0;
87 	niceness += getpriority(PRIO_PROCESS, 0);
88 	if (errno)
89 		err(1, "getpriority");
90 	if (setpriority(PRIO_PROCESS, 0, niceness))
91 		err(1, "setpriority");
92 	execvp(argv[1], &argv[1]);
93 	err(1, "%s", argv[1]);
94 }
95 
96 void
97 usage()
98 {
99 	(void)fprintf(stderr, "usage: nice [-number] command [arguments]\n");
100 	exit(1);
101 }
102