keyboard_ucallback(3)           Allegro manual           keyboard_ucallback(3)



NAME
       keyboard_ucallback - User specified unicode keyboard callback handler.
       Allegro game programming library.

SYNOPSIS
       #include <allegro.h>


       extern int (*keyboard_ucallback)(int key, int *scancode);

DESCRIPTION
       Unicode-aware version of keyboard_callback(). If set, this function is
       called by the keyboard handler in response to every keypress. It is
       passed the character value and scancode that are about to be added into
       the input buffer, can modify the scancode value, and returns a new or
       modified key code. If it both sets the scancode to zero and returns
       zero, the keypress will be ignored. This routine executes in an
       interrupt context, so it must be in locked memory. Example:

          int silence_g_key(int key, int *scancode)
          {
             if (key == 'g') {
                *scancode = 0;
                return 0;
             }
             return key;
          } END_OF_FUNCTION(silence_g_key)

          ...

             install_timer();
             LOCK_FUNCTION(silence_g_key);
             install_keyboard();
             keyboard_ucallback = silence_g_key;

       Note that this keyboard callback has priority over the non unicode
       callback. If you set both, only the unicode one will work.


SEE ALSO
       install_keyboard(3), readkey(3), ureadkey(3), keyboard_callback(3),
       keyboard_lowlevel_callback(3)



Allegro                          version 4.2.3           keyboard_ucallback(3)
