install_int - Installs a user timer handler. Allegro game programming library.

       Installs  a user timer handler, with the speed given as the number of milliseconds between ticks. This is
       the same thing as install_int_ex(proc, MSEC_TO_TIMER(speed)). If you call  this  routine  without  having
       first  installed  the  timer  module,  install_timer()  will  be called automatically. Calling again this
       routine with the same timer handler as parameter allows you to adjust its speed.

       install_int - Installs a user timer handler. Allegro game programming library.

       Returns zero on success, or a negative number if there is no room to add a new user timer.

install_timer(3alleg4),   remove_int(3alleg4),    install_int_ex(3alleg4),    install_param_int(3alleg4),
       exscn3d(3alleg4), exswitch(3alleg4), extimer(3alleg4), exzbuf(3alleg4)

Allegro                                           version 4.4.3                             install_int(3alleg4)

#include<allegro.h>intinstall_int(void(*proc)(),intspeed);