projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 1a51a8f3 BJ |
1 | #include <sys/param.h> |
| 2 | #include <sys/proc.h> | |
| 3 | #include <stdio.h> | |
| 4 | ||
| 5 | struct proc proc[NPROC]; | |
| 6 | struct { | |
| 7 | char name[8]; | |
| 8 | int type; | |
| 9 | unsigned value; | |
| 10 | } nl[] = { | |
| 11 | "_proc", 0, 0, | |
| 12 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 | |
| 13 | }; | |
| 14 | ||
| 15 | /* | |
| 16 | * Change the running priority (nice) of a process which is already | |
| 17 | * running. | |
| 18 | * | |
| 19 | * Author: Kurt Shoens | |
| 20 | */ | |
| 21 | ||
| 22 | main(argc, argv) | |
| 23 | char **argv; | |
| 24 | { | |
| 25 | register struct proc *pp; | |
| 26 | int pid, nice; | |
| 27 | int addr, mem, a1, a2, coreaddr; | |
| 28 | ||
| 29 | if (argc != 2 && argc != 3) { | |
| 30 | fprintf(stderr, "usage: renice pid [ priority ]\n"); | |
| 31 | exit(1); | |
| 32 | } | |
| 33 | if (geteuid()) { | |
| 34 | fprintf(stderr, "NOT super user\n"); | |
| 35 | exit(1); | |
| 36 | } | |
| 37 | pid = atoi(argv[1]); | |
| 38 | nice = atoi(argc == 3 ? argv[2] : "19"); | |
| 39 | if (nice > 20) | |
| 40 | nice = 20; | |
| 41 | if (nice < -20) | |
| 42 | nice = -20; | |
| 43 | nice += NZERO; | |
| 44 | mem = open("/dev/kmem", 2); | |
| 45 | if (mem < 0) { | |
| 46 | perror("/dev/kmem"); | |
| 47 | exit(1); | |
| 48 | } | |
| 49 | nlist("/vmunix", nl); | |
| 50 | addr = nl[0].value; | |
| 51 | if (addr == 0) { | |
| 52 | fprintf(stderr, "/vmunix: _proc not in namelist"); | |
| 53 | exit(1); | |
| 54 | } | |
| 55 | lseek(mem, addr, 0); | |
| 56 | read(mem, &proc[0], sizeof proc); | |
| 57 | for (pp = &proc[0]; pp < &proc[NPROC]; pp++) | |
| 58 | if (pp->p_pid == pid) | |
| 59 | break; | |
| 60 | if (pp >= &proc[NPROC]) { | |
| 61 | fprintf(stderr, "%d: process not found\n", pid); | |
| 62 | exit(1); | |
| 63 | } | |
| 64 | fprintf(stderr, "%d: old nice = %d, new nice = %d\n", | |
| 65 | pid, | |
| 66 | pp->p_nice - NZERO, | |
| 67 | nice - NZERO); | |
| 68 | a1 = (int)&pp->p_nice; | |
| 69 | a2 = (int)&proc[0]; | |
| 70 | coreaddr = a1-a2+addr; | |
| 71 | lseek(mem, (long)coreaddr, 0); | |
| 72 | write(mem, &nice, 1); | |
| 73 | } |