Reading Key Up with the PS/2 Library

Hi there!

So I've been mucking around with an old ps2 Keyboard using the PS/2 Library.

By now, I'm calling keyboard.read() to get an ascii code of the key that I'm pressing on the ps/2 keyboard. This is working perfectly fine.
The problem that I have is that I just can't receive a "key up" or a "key break" signal.
Something so that I could see if the key has been let go...

Is this even possible with the library?

In the keywords.txt of the library, I found this line:

PS2_KC_BREAK LITERAL1

though, when I try to implement it into the code, I just get the error message:

"ps2Keyboard_2.ino:41:14: error: 'PS2_KC_BREAK' was not declared in this scope
Error compiling."

Here's a shortened version of the code:
(For background information on what the scetch should do: I'm trying to receive keyboard input from the ps2 keyboard. I'll then flash the arduino like this, so that it will appear as a standard usb keyboard, thus enabling me to interact with the keyboard input...


#include <PS2Keyboard.h>

const int DataPin = 2; // Yellow wire
const int IRQpin =  3; // Green wire

uint8_t buf[8] = {0};

PS2Keyboard keyboard;

void setup() {
  delay(1000);
  keyboard.begin(DataPin, IRQpin, PS2Keymap_German);
  Serial.begin(9600);
  pinMode(ledPin, OUTPUT);
  pinMode(servicePin, INPUT);
}

void loop() {
  
  if (keyboard.available()) {
    char c = keyboard.read();
    
    ///// WASD Control
    if (c == 'a' || c == 'A') pressKey(4);
    if (c == 'b' || c == 'B') pressKey(5);
    if (c == 'd' || c == 'D') pressKey(7);
    if (c == 'w' || c == 'W') pressKey(26);
    if (c == 's' || c == 'S') pressKey(22);
    
    ////// Special Keys
    if (c == PS2_ESC) pressKey(41);
    
    
    ////// Arrows
    if (c == PS2_LEFTARROW)  pressKey(92);
    if (c == PS2_RIGHTARROW) pressKey(94);
    if (c == PS2_UPARROW)    pressKey(96);
    if (c == PS2_DOWNARROW)  pressKey(90);
  
    ////Release the key
    if (c == PS2_KC_BREAK) releaseKey();
  }
}

void pressKey(int key) {
  buf[2] = key;
  Serial.write(buf, 8);
}

void releaseKey() {
  //Serial.println();
  buf[0] = 0;
  buf[2] = 0;
  Serial.write(buf, 8);	// Release key  
}

Something so that I could see if the key has been let go...

Wouldn't that be the case if keyboard.available() returned 0 (or false)?