#pragma section-numbers off
#pragma camelcase off

= SDL_CondWaitTimeout =
Use this function to wait until a condition variable is signaled or a specified amount of time has passed.

<<TableOfContents()>>

== Syntax ==
{{{#!highlight cpp
int SDL_CondWaitTimeout(SDL_cond*  cond,
                        SDL_mutex* mutex,
                        Uint32     ms)
}}}
== Function Parameters ==
||'''cond''' ||the condition variable to wait on||
||'''mutex''' ||the mutex used to coordinate thread access||
||'''ms''' ||the maximum time to wait in milliseconds, or SDL_MUTEX_MAXWAIT to wait indefinitely||

== Return Value ==
Returns 0 if the condition variable is signaled, SDL_MUTEX_TIMEDOUT if the condition is not signaled in the allotted time, or a negative error code on failure; call [[SDL_GetError]]() for more information.

== Code Examples ==
{{{#!highlight cpp
SDL_bool condition = SDL_FALSE;
SDL_mutex *lock;
SDL_cond *cond;

lock = SDL_CreateMutex();
cond = SDL_CreateCond();
.
.
Thread A:
    const Uint32 timeout = 1000; /* wake up every second */

    while (!done) {
        SDL_LockMutex(lock);
        while (!condition && SDL_CondWaitTimeout(cond, lock, timeout) == 0) {
            continue;
        }
        SDL_UnlockMutex(lock);

        if (condition) {
            ...
        }

        ... do some periodic work
    }

Thread B:
    SDL_LockMutex(lock);
    ...
    condition = SDL_TRUE;
    ...
    SDL_CondSignal(cond);
    SDL_UnlockMutex(lock);
.
.
SDL_DestroyCond(cond);
SDL_DestroyMutex(lock);
}}}

== Remarks ==
This function unlocks the specified '''mutex''' and waits for another thread to call [[SDL_CondSignal]]() or [[SDL_CondBroadcast]]() on the condition variable '''cond''', or for the specified time to elapse.  Once the condition variable is signaled or the time elapsed, the mutex is re-locked and the function returns.

The mutex must be locked before calling this function.

== Related Functions ==
 .[[SDL_CondBroadcast]]
 .[[SDL_CondSignal]]
 .[[SDL_CondWait]]
 .[[SDL_CreateCond]]
 .[[SDL_DestroyCond]]

----
[[CategoryAPI]], [[CategoryMutex]]