1 .TH "SDL_SetTimer" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 

     2 .SH "NAME"

     3 SDL_SetTimer \- Set a callback to run after the specified number of milliseconds has elapsed\&.

     4 .SH "SYNOPSIS"

     5 .PP

     6 \fB#include "SDL\&.h"

     7 .sp

     8 \fBint \fBSDL_SetTimer\fP\fR(\fBUint32 interval, SDL_TimerCallback callback\fR);

     9 .SH "CALLBACK"

    10 .PP

    11 /* Function prototype for the timer callback function */ typedef Uint32 (*SDL_TimerCallback)(Uint32 interval);

    12 .SH "DESCRIPTION"

    13 .PP

    14 Set a callback to run after the specified number of milliseconds has elapsed\&. The callback function is passed the current timer interval and returns the next timer interval\&. If the returned value is the same as the one passed in, the periodic alarm continues, otherwise a new alarm is scheduled\&.

    15 .PP

    16 To cancel a currently running timer, call \fBSDL_SetTimer(0, NULL);\fP

    17 .PP

    18 The timer callback function may run in a different thread than your main constant, and so shouldn\&'t call any functions from within itself\&.

    19 .PP

    20 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)\&.

    21 .PP

    22 If you use this function, you need to pass \fBSDL_INIT_TIMER\fP to \fBSDL_Init()\fP\&.

    23 .PP

    24 .RS

    25 \fBNote:  

    26 .PP

    27 This function is kept for compatibility but has been superseded by the new timer functions \fISDL_AddTimer\fR and \fISDL_RemoveTimer\fR which support multiple timers\&.

    28 .RE

    29 .SH "EXAMPLES"

    30 .PP

    31 .PP

    32 .nf

    33 \f(CWSDL_SetTimer((33/10)*10, my_callback);\fR

    34 .fi

    35 .PP

    36 .SH "SEE ALSO"

    37 .PP

    38 \fI\fBSDL_AddTimer\fP\fR

    39 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01