1 /* vi: set sw=4 ts=4: */
3 * nice implementation for busybox
5 * Copyright (C) 2005 Manuel Novoa III <mjn3@codepoet.org>
7 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
10 #include <sys/resource.h>
13 int nice_main(int argc, char **argv)
15 int old_priority, adjustment;
17 old_priority = getpriority(PRIO_PROCESS, 0);
19 if (!*++argv) { /* No args, so (GNU) output current nice value. */
20 printf("%d\n", old_priority);
21 fflush_stdout_and_exit(EXIT_SUCCESS);
24 adjustment = 10; /* Set default adjustment. */
26 if (argv[0][0] == '-') {
27 if (argv[0][1] == 'n') { /* -n */
28 if (argv[0][2]) { /* -nNNNN (w/o space) */
29 argv[0] += 2; argv--; argc++;
31 } else { /* -NNN (NNN may be negative) == -n NNN */
32 argv[0] += 1; argv--; argc++;
34 if (argc < 4) { /* Missing priority and/or utility! */
37 adjustment = xatoi_range(argv[1], INT_MIN/2, INT_MAX/2);
41 { /* Set our priority. */
42 int prio = old_priority + adjustment;
44 if (setpriority(PRIO_PROCESS, 0, prio) < 0) {
45 bb_perror_msg_and_die("setpriority(%d)", prio);
49 execvp(*argv, argv); /* Now exec the desired program. */
51 /* The exec failed... */
52 xfunc_error_retval = (errno == ENOENT) ? 127 : 126; /* SUSv3 */
53 bb_perror_msg_and_die("%s", *argv);