Configure key repeat delay to detect if key is being pressed

Question

I am writing a program in C that uses ncurses to check if a key is being pressed. The problem is that there is a key repeat delay.

If I for example hold the key \'a\

Answer 1

Try this to ignore buffered key repeats:

int key;
if ((key = getch()) != ERR) {
  while (getch() == key);
}

In context:

//example.c

#include 
#include 

int main(int argc, char *argv[]) {
  int pos_x = 0;
  int max_x = 0, max_y = 0;
  int key = 0;
  int on = 1;

  initscr();
  noecho();
  cbreak();
  curs_set(FALSE);
  keypad(stdscr, TRUE);
  nodelay(stdscr, TRUE);
  getmaxyx(stdscr,max_y,max_x);

  while(1) {
    clear();
    mvprintw(0, 0, "Press, hold and release L-R arrow keys. Press UP/DOWN to toggle function.");
    mvprintw(1, 0, "Skip buffered repeats: %s", (on ? "ON" : "OFF"));
    mvprintw(2, pos_x, "@");
    refresh();
    usleep(50000);
    getmaxyx(stdscr,max_y,max_x);
    key = getch();

    // skip buffered repeats                                                                                     
    if (on) {
      if (key != ERR) {
        while (getch() == key);
      }
    }
    //                                                                                                           

    switch (key) {
    case KEY_LEFT:
      pos_x += (pos_x > 0 ? -1 : 0); break;
    case KEY_RIGHT:
      pos_x += (pos_x < max_x - 1 ? 1 : 0); break;
    case KEY_UP:
      on = 1; break;
    case KEY_DOWN:
      on = 0; break;
    }
  }
  endwin();
}

Compile and run with gcc example.c -lncurses -oexample && ./example