*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+
+//usage:#define chrt_trivial_usage
+//usage: "[-prfom] [PRIO] [PID | PROG ARGS]"
+//usage:#define chrt_full_usage "\n\n"
+//usage: "Change scheduling priority and class for a process\n"
+//usage: "\n -p Operate on PID"
+//usage: "\n -r Set SCHED_RR class"
+//usage: "\n -f Set SCHED_FIFO class"
+//usage: "\n -o Set SCHED_OTHER class"
+//usage: "\n -m Show min/max priorities"
+//usage:
+//usage:#define chrt_example_usage
+//usage: "$ chrt -r 4 sleep 900; x=$!\n"
+//usage: "$ chrt -f -p 3 $x\n"
+//usage: "You need CAP_SYS_NICE privileges to set scheduling attributes of a process"
+
#include <sched.h>
#include "libbb.h"
-#ifndef _POSIX_PRIORITY_SCHEDULING
-#warning your system may be foobared
-#endif
static const struct {
int policy;
const char *current_new;
int policy = SCHED_RR;
- /* at least 1 arg; only one policy accepted */
- opt_complementary = "-1:r--fo:f--ro:o--rf";
+ /* only one policy accepted */
+ opt_complementary = "r--fo:f--ro:o--rf";
opt = getopt32(argv, "+mprfo");
+ if (opt & OPT_m) { /* print min/max and exit */
+ show_min_max(SCHED_FIFO);
+ show_min_max(SCHED_RR);
+ show_min_max(SCHED_OTHER);
+ fflush_stdout_and_exit(EXIT_SUCCESS);
+ }
if (opt & OPT_r)
policy = SCHED_RR;
if (opt & OPT_f)
policy = SCHED_FIFO;
if (opt & OPT_o)
policy = SCHED_OTHER;
- if (opt & OPT_m) { /* print min/max */
- show_min_max(SCHED_FIFO);
- show_min_max(SCHED_RR);
- show_min_max(SCHED_OTHER);
- fflush_stdout_and_exit(EXIT_SUCCESS);
- }
argv += optind;
+ if (!argv[0])
+ bb_show_usage();
if (opt & OPT_p) {
pid_str = *argv++;
if (*argv) { /* "-p <priority> <pid> [...]" */