(This is the documentation for SDL3, which is under heavy development and the API is changing! SDL2 is the current stable version!)

SDL_TryLockRWLockForWriting

Try to lock a read/write lock for writing without blocking.

Header File

Syntax

int SDL_TryLockRWLockForWriting(SDL_RWLock *rwlock) SDL_TRY_ACQUIRE(0, rwlock);

Function Parameters

rwlock

the rwlock to try to lock

Return Value

Returns 0 or SDL_RWLOCK_TIMEDOUT

Remarks

This works just like SDL_LockRWLockForWriting(), but if the rwlock is not available, this function returns SDL_RWLOCK_TIMEDOUT immediately.

This technique is useful if you need exclusive access to a resource but don't want to wait for it, and will return to it to try again later.

It is illegal for the owning thread to lock an already-locked rwlock for writing (read-only may be locked recursively, writing can not). Doing so results in undefined behavior.

It is illegal to request a write lock from a thread that already holds a read-only lock. Doing so results in undefined behavior. Unlock the read-only lock before requesting a write lock.

This function does not fail; if rwlock is NULL, it will return 0 immediately having locked nothing. If rwlock is valid, this function will always either lock the rwlock and return 0, or return SDL_RWLOCK_TIMEOUT and lock nothing.

Version

This function is available since SDL 3.0.0.