Virtual Keyboard (Linux/libevdev) - sending events

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Trying to implement a virtual keyboard. The program sends a keystroke event in the 5 second cycle. Its working on PC (Ubuntu Linux). The problem is that nothing is displayed on BBB.

Plaftorm Beaglebone Black, Debian Jessie:

debian@beaglebone:~$ uname -a
Linux beaglebone 4.9.9-ti-r22 #1 SMP PREEMPT Mon Feb 13 18:39:00 UTC 2017 armv7l GNU/Linux

`
Code:#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <string.h>
#include <linux/uinput.h>

/* emit function is identical to of the first example */

void emit(int fd, int type, int code, int val)
{
struct input_event ie;

ie.type = type;
ie.code = code;
ie.value = val;
/* timestamp values below are ignored */
ie.time.tv_sec = 0;
ie.time.tv_usec = 0;

int res = write(fd, &ie, sizeof(ie));
printf(“emit write bytes=%d fd=%d code=%d val=%d\n”,res, fd, code, val);
}

int main(void)
{
struct uinput_user_dev uud;
int version, rc, fd;

fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK);
printf(“fd=%d\n”,fd);

/*

  • The ioctls below will enable the device that is about to be
  • created, to pass key events, in this case the space key.
    */
    int i1 = ioctl(fd, UI_SET_EVBIT, EV_KEY);
    int i2 = ioctl(fd, UI_SET_EVBIT, EV_SYN);
    int i3 = ioctl(fd, UI_SET_KEYBIT, KEY_D);
    int i4 = ioctl(fd, UI_SET_KEYBIT, KEY_U);
    int i5 = ioctl(fd, UI_SET_KEYBIT, KEY_P);
    int i6 = ioctl(fd, UI_SET_KEYBIT, KEY_A);

// printf(“ioctl = %d, %d, %d ,%d , %d, %d\n”, i1,i2,i3,i4,i5,i6);

memset(&uud, 0, sizeof(uud));
snprintf(uud.name, UINPUT_MAX_NAME_SIZE, “uinput-keyboard”);
uud.id.bustype = BUS_HOST;
uud.id.vendor = 0x1;
uud.id.product = 0x2;
uud.id.version = 1;

write(fd, &uud, sizeof(uud));
sleep(2);

int i = ioctl(fd, UI_DEV_CREATE);
printf(“dev create =%d\n”, i);

sleep(2);

/* Key press, report the event, send key release, and report again */
for(;:wink:
{
emit(fd, EV_KEY, KEY_D, 1);
emit(fd, EV_SYN, SYN_REPORT, 1);
sleep(1);
emit(fd, EV_KEY, KEY_D, 0);
emit(fd, EV_SYN, SYN_REPORT, 0);

emit(fd, EV_KEY, KEY_U, 1);
emit(fd, EV_SYN, SYN_REPORT, 0);
emit(fd, EV_KEY, KEY_U, 0);
emit(fd, EV_SYN, SYN_REPORT, 0);

emit(fd, EV_KEY, KEY_P, 1);
emit(fd, EV_SYN, SYN_REPORT, 0);
emit(fd, EV_KEY, KEY_P, 0);
emit(fd, EV_SYN, SYN_REPORT, 0);

emit(fd, EV_KEY, KEY_A, 1);
emit(fd, EV_SYN, SYN_REPORT, 0);
emit(fd, EV_KEY, KEY_A, 0);
emit(fd, EV_SYN, SYN_REPORT, 0);

sleep(5);
}
ioctl(fd, UI_DEV_DESTROY);

close(fd);
return 0;
}

`