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Revision 12 as of 2013-10-05 20:43:25
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Revision 13 as of 2013-10-13 12:31:34
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Comment: Added missing thread name for SDL_CreateThread() in example.
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    thread = SDL_CreateThread(TestThread, (void *)NULL);     thread = SDL_CreateThread(TestThread, "TestThread", (void *)NULL);


Use this function to wait for a thread to finish.


void SDL_WaitThread(SDL_Thread* thread,
                    int*        status)

Function Parameters


the SDL_Thread pointer that was returned from the SDL_CreateThread() call that started this thread


pointer to an integer that will receive the value returned from the thread function by its 'return', see Remarks for details

Code Examples

#include <stdio.h>
#include <SDL_thread.h>
#include <SDL_timer.h>

int TestThread(void *ptr);

int main(int argc, char *argv[])
    SDL_Thread *thread;
    int         threadReturnValue;

    printf("\nSimple SDL_CreateThread test:");

    // Simply create a thread
    thread = SDL_CreateThread(TestThread, "TestThread", (void *)NULL);

    if (NULL == thread) {
        printf("\nSDL_CreateThread failed: %s\n", SDL_GetError());
    } else {
        // Wait for the thread to complete. The thread functions return code will
        //       be placed in the "threadReturnValue" variable when it completes.
        SDL_WaitThread(thread, &threadReturnValue);
        printf("\nThread returned value:%d", threadReturnValue);

    return 1;

// Very simple thread - counts 0 to 9 delaying 50ms between increments
int TestThread(void *ptr)
    int        cnt;

    for (cnt = 0; cnt < 10; cnt++) {
        printf("\nThread counter: %d", cnt);

    // Return the final value to the SDL_WaitThread function above
    return cnt;


The return code for the thread function is placed in the area pointed to by status, if status is not NULL. The return code is the value returned by the 'return' statement in the thread function.

Note that the thread pointer is freed by this function and is not valid afterward.

CategoryAPI, CategoryThread

None: SDL_WaitThread (last edited 2018-12-12 14:53:52 by RyanGordon)

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