Lock the read/write lock for write operations.
void SDL_LockRWLockForWriting(SDL_RWLock *rwlock) SDL_ACQUIRE(rwlock);
|rwlock||the read/write lock to lock|
This will block until the rwlock is available, which is to say it is not locked for reading or writing by any other thread. Only one thread may hold the lock when it requests write access; all other threads, whether they also want to write or only want read-only access, must wait until the writer thread has released the lock.
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 immediately having locked nothing. If the rwlock is valid, this function will always block until it can lock the mutex, and return with it locked.
This function is available since SDL 3.0.0.