# PR_NotifyAllCondVar Notifies all of the threads waiting on a specified condition variable. ## Syntax ```{code} #include PRStatus PR_NotifyAllCondVar(PRCondVar *cvar); ``` ### Returns The function returns one of the following values: - If successful, `PR_SUCCESS`. - If unsuccessful (for example, if the caller has not locked the lock associated with the condition variable), `PR_FAILURE`. ## Description The calling thread must hold the lock that protects the condition, as well as the invariants that are tightly bound to the condition. A call to {ref}`PR_NotifyAllCondVar` causes all of the threads waiting on the specified condition variable to be promoted to a ready state. If no threads are waiting, the operation is no-op.