osx man page for three_finger_flag

three_finger_flag(3alleg4)					  Allegro manual					three_finger_flag(3alleg4)

NAME
       three_finger_flag - Flag to deactivate the emergency exit key combination. Allegro game programming library.

SYNOPSIS
       #include <allegro.h>

       extern int three_finger_flag;

DESCRIPTION
       The  DJGPP  keyboard handler provides an 'emergency exit' sequence which you can use to kill off your program. If you are running under DOS
       this is the three finger salute, ctrl+alt+del. Most multitasking OS's will trap this combination before it reaches the Allegro handler,	in
       which  case  you  can use the alternative ctrl+alt+end. If you want to disable this behaviour in release versions of your program, set this
       flag to FALSE.

SEE ALSO
       install_keyboard(3alleg4)

Allegro 							   version 4.4.2					three_finger_flag(3alleg4)