Cannot generate keystroke written to device kernel with input.h Linux - linux

Question

I am trying to generate keystrokes and write them to the kernel in Linux using the input library. I found an example form http://rico-studio.com/linux/read-and-write-to-a-keyboard-device/ and made a little test program. It should just print a bunch of t's but only does this when I strike a key (space for example) myself.
#include <linux/input.h>
#include <linux/uinput.h>
#include <fcntl.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#define EV_PRESSED 1
#define EV_RELEASED 0
#define EV_REPEAT 2
int main() {
int fd = 0;
/*In my case event3 handles the keyboard. This can be checked typing
* cat /proc/bus/input/devices in the terminal
*/
char *device = "/dev/input/event3";
struct input_event event;
memset(&event, 0, sizeof(event));
gettimeofday(&event.time, NULL);
if( (fd = open(device, O_RDWR | O_NONBLOCK )) < 0 )
{
printf("not opened "); // Read or Write to device
return 0;
}
for(int i=0;i <500 ;i++)
{
// usleep(1000);
event.type = EV_KEY;
// Press the key down
event.value = EV_PRESSED;
event.code = KEY_T;
write(fd, &event, sizeof(struct input_event));
// usleep(1000);
// Release the key
event.value = EV_RELEASED;
event.code = KEY_T;
write(fd, &event, sizeof(struct input_event));
usleep(100000);
}
close(fd);
return 0;
}
Maybe this key-stroke flushes the memory along with the generated keystrokes for t written to the devices memory? So I am wondering what I am missing to let it generate a keystroke and write it to the kernel all by itself.

Answer 1

If you run xxd /dev/input3 and break apart the output, you can see that the keyboard is also sending EV_SYN, SYN_REPORT events after each key change to mark the end of a grouped set of events. To do the same:
event.type = EV_SYN;
event.code = SYN_REPORT;
event.value = 0;
write(fd, &event, sizeof(struct input_event));