Hi,

I'm trying to code a KeyBoard Emulator for Linux (based on jtyrrell, a member of this forum), first I thought to use python to achieve it, but all the libraries were using X (and I don't want to use it). I decided to code in C++ to write in the keyboard buffer. After a few days of learning C and doing some research on Linux and how the input system works, I came up with this:

#include <stdio.h>
#include <fcntl.h>
#include <linux/input.h>
#include <sstream>
#include <unistd.h>

#define EV_PRESSED 1
#define EV_RELEASED 0

int Emulate(char character)
{
printf("Starting the keyboard buffer writer\n");


int fd = 0;
char *device = "/dev/input/event1";

if( (fd = open(device, O_RDWR)) > 0 )
{

struct input_event event;
printf("The keyboard code is: %d \n", KEY_A);

event.type = EV_KEY;
event.value = EV_PRESSED;
event.code = KEY_A;
write(fd, &event, sizeof(struct input_event));

event.value = EV_RELEASED;
event.code = KEY_A;
write(fd, &event, sizeof(struct input_event));
close(fd);
}
return 0;
}


int main(int argc, char *argv[]){
for(int i=0; i < sizeof(argv[1])/sizeof(int); i++){
Emulate(argv[1][i]);//for each car in the argv 1 call Emulate
}
}
As you can see I'm writing manually KEY_A to press the a key. And I was wondering if there is a function or a way to change a char to the keycodes defined in the file /usr/include/linux/input-event-codes.h.

Thank you for your help !

Just FYI, there is already a program that does that: xdotool
https://www.semicomplete.com/projects/xdotool/

It comes with a library in C, maybe you could use it to make your own program

Edit: Oh you don't want to use X, sorry...
Maybe use a character codes array and a character value / array index mapping

PS: your program is in C not in C++

1 members found this post helpful.

Damn Xorg

Thanks for the advice, I ended up doing a big dictionary in a Python script, and then this script launches the C program!