A mutex that allows read-only threads to run in parallel.
Defined in <SDL3/SDL_mutex.h>
typedef struct SDL_RWLock SDL_RWLock;
A rwlock is roughly the same concept as SDL_Mutex, but allows threads that request read-only access to all hold the lock at the same time. If a thread requests write access, it will block until all read-only threads have released the lock, and no one else can hold the thread (for reading or writing) at the same time as the writing thread.
This can be more efficient in cases where several threads need to access data frequently, but changes to that data are rare.
There are other rules that apply to rwlocks that don't apply to mutexes, about how threads are scheduled and when they can be recursively locked. These are documented in the other rwlock functions.
This struct is available since SDL 3.1.3.