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SDL_AddTimer(3)		       SDL API Reference	       SDL_AddTimer(3)

NAME
       SDL_AddTimer  - Add a timer which will call a callback after the	speci-
       fied number of milliseconds has elapsed.

SYNOPSIS
       #include	"SDL.h"

       SDL_TimerID SDL_AddTimer(Uint32	interval,  SDL_NewTimerCallback	 call-
       back, void *param);

CALLBACK
       /* type definition for the "new"	timer callback function	*/
       typedef Uint32 (*SDL_NewTimerCallback)(Uint32 interval, void *param);

DESCRIPTION
       Adds  a	callback function to be	run after the specified	number of mil-
       liseconds has elapsed. The callback  function  is  passed  the  current
       timer  interval	and  the user supplied parameter from the SDL_AddTimer
       call and	returns	the next timer interval. If the	 returned  value  from
       the  callback is	the same as the	one passed in, the periodic alarm con-
       tinues, otherwise a new alarm is	scheduled.

       To cancel a currently running timer call	SDL_RemoveTimer	with the timer
       ID returned from	SDL_AddTimer.

       The  timer  callback  function  may run in a different thread than your
       main program, and so shouldn't call any functions from  within  itself.
       You may always call SDL_PushEvent, however.

       The  granularity	 of  the  timer	 is platform-dependent,	but you	should
       count on	it being at least 10 ms	as this	is  the	 most  common  number.
       This  means  that  if you request a 16 ms timer,	your callback will run
       approximately 20	ms later on an unloaded	system.	If you wanted to set a
       flag  signaling	a  frame update	at 30 frames per second	(every 33 ms),
       you might set a timer for 30 ms (see example below). If	you  use  this
       function, you need to pass SDL_INIT_TIMER to SDL_Init.

RETURN VALUE
       Returns an ID value for the added timer or NULL if there	was an error.

EXAMPLES
       my_timer_id = SDL_AddTimer((33/10)*10, my_callbackfunc, my_callback_param);

SEE ALSO
       SDL_RemoveTimer,	SDL_PushEvent

SDL			    Tue	11 Sep 2001, 23:01	       SDL_AddTimer(3)

NAME | SYNOPSIS | CALLBACK | DESCRIPTION | RETURN VALUE | EXAMPLES | SEE ALSO

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