SDL_SetTimer(3) SDL API Reference SDL_SetTimer(3)NAME
SDL_SetTimer- Set a callback to run after the specified
number of milliseconds has elapsed.
SYNOPSIS
#include "SDL.h"
int SDL_SetTimer(Uint32 interval, SDL_TimerCallback call-
back);
CALLBACK
/* Function prototype for the timer callback function */
typedef Uint32 (*SDL_TimerCallback)(Uint32 interval);
DESCRIPTION
Set a callback to run after the specified number of mil-
liseconds has elapsed. The callback function is passed the
current timer interval and returns the next timer inter-
val. If the returned value is the same as the one passed
in, the periodic alarm continues, otherwise a new alarm is
scheduled.
To cancel a currently running timer, call SDL_SetTimer(0,
NULL);
The timer callback function may run in a different thread
than your main constant, and so shouldn't call any func-
tions from within itself.
The maximum resolution of this timer is 10 ms, which 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().
Note:
This function is kept for compatibility but has
been superseded by the new timer functions
SDL_AddTimer and SDL_RemoveTimer which support mul-
tiple timers.
EXAMPLES
SDL_SetTimer((33/10)*10, my_callback);
SEE ALSO
SDL_AddTimer
SDL Tue 11 Sep 2001, 23:01 SDL_SetTimer(3)
