#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
int main(int argc,char **argv) {
int fd;
unsigned char key_vals[4];
int cnt=0;
fd=open("/dev/buttons",O_RDWR );
//这个 " /dev/xxx" 后面不能有空格
if (fd<0) {
printf("can\'t open!\n");
} while (1) {
read (fd, key_vals,sizeof(key_vals));
if (!key_vals[0] || !key_vals[1] || key_vals[2] ||key_vals[3] ) {
printf ("%04d key pressed:%d %d %d %d\n",cnt++, key_vals[0],key_vals[1],key_vals[2],key_vals[3] );
}
}
return 0;
}