37 lines
659 B
C
37 lines
659 B
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
void usage() {
|
|
fprintf(stderr, "Usage: setpinebacklight [0-10]\n");
|
|
}
|
|
|
|
int main(int argc, char *argv[]) {
|
|
char * command;
|
|
int brightness;
|
|
|
|
if (argc < 2) {
|
|
usage();
|
|
return 1;
|
|
}
|
|
argc--;
|
|
brightness = atoi(argv[argc--]);
|
|
|
|
if (brightness < 0 || brightness > 10) {
|
|
usage();
|
|
return 1;
|
|
}
|
|
|
|
command = malloc(100);
|
|
sprintf(
|
|
command,
|
|
"sh -c 'echo %d > /sys/devices/platform/backlight/backlight/backlight/brightness'",
|
|
brightness
|
|
);
|
|
if (setuid(0)) {
|
|
fprintf(stderr, "setuid(0) failed\n");
|
|
} else {
|
|
return system(command);
|
|
}
|
|
}
|