-
Notifications
You must be signed in to change notification settings - Fork 0
/
forkd.c
80 lines (69 loc) · 1.47 KB
/
forkd.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
int main(int argc, char **argv)
{
int fd;
char string[300];
char old_cmd[300];
int br;
int ppid = 0, pid;
// Open the silverware drawer
fd = open("/proc/loadavg", O_RDONLY);
if (fd < 0) {
perror("/proc/loadavg");
exit(EXIT_FAILURE);
}
while (1) {
// Grab a fork
memset(string, 0, 300);
memset(old_cmd, 0, 300);
br = pread(fd, string, 300, 0);
if (!br) {
fprintf(stderr, "read zero bytes!\n");
close(fd);
exit(EXIT_FAILURE);
}
sscanf(string, "%*f %*f %*f %*s %i", &pid);
// Never use the same fork twice
if (ppid != pid) {
int x;
size_t needed;
char *buffer;
ppid = pid;
printf("%i: ", pid);
fflush(stdout);
needed = snprintf(NULL, 0, "/proc/%i/cmdline", pid) + 1;
buffer = malloc(needed);
snprintf(buffer, needed, "/proc/%i/cmdline", pid);
for (x = 0; x < 10; x++) {
int i, cfd;
cfd = open(buffer, O_RDONLY);
if (cfd < 0) {
// TODO: ignore errors for now
//perror(buffer);
continue;
}
memset(string, 0, 300);
br = pread(cfd, string, 300, 0);
for (i = 0; i < br && i < (300-1); i++) {
if (string[i] == '\0')
string[i] = ' ';
}
if (strcmp(string, old_cmd)) {
printf("\t%s\n", string);
}
memcpy(old_cmd, string, 300);
close(cfd);
usleep(100);
}
free(buffer);
}
usleep(1000);
}
close(fd);
exit(EXIT_SUCCESS);
}