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keyboard_callback(3) Allegro manual keyboard_callback(3) NAME keyboard_callback - User specified keyboard callback handler. Allegro game programming library. SYNOPSIS #include <allegro.h> extern int (*keyboard_callback)(int key); DESCRIPTION If set, this function is called by the keyboard handler in response to every keypress. It is passed a copy of the value that is about to be added into the input buffer, and can either return this value un- changed, return zero to cause the key to be ignored, or return a modi- fied value to change what readkey() will later return. This routine ex- ecutes in an interrupt context, so it must be in locked memory. Exam- ple: int enigma_scrambler(int key) { /* Add one to both the scancode and ascii values. */ return (((key >> 8) + 1) } END_OF_FUNCTION(enigma_scrambler) ... install_timer(); LOCK_FUNCTION(enigma_scrambler); install_keyboard(); keyboard_callback = enigma_scrambler; Note that this callback will be ignored if you also set the unicode keyboard callback. SEE ALSO install_keyboard(3), readkey(3), ureadkey(3), keyboard_ucallback(3), keyboard_lowlevel_callback(3) Allegro version 4.4.3 keyboard_callback(3)
NAME | SYNOPSIS | DESCRIPTION | SEE ALSO
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