# PR_CNotifyAll Notifies all the threads waiting for a change in the state of monitored data. ## Syntax ```{code} #include PRStatus PR_CNotifyAll(void *address); ``` ### Parameter The function has the following parameter: `address` : The address of the monitored object. The calling thread must be in the monitor at the time {ref}`PR_CNotifyAll` is called. ### Returns > - `PR_SUCCESS` indicates that the referenced monitor was located and > the calling thread was in the monitor. > - `PR_FAILURE` indicates that the referenced monitor could not be > located or that the calling thread was not in the monitor ## Description Using the value specified in the address parameter to find a monitor in the monitor cache, {ref}`PR_CNotifyAll` notifies all threads waiting for the monitor's state to change. All of the threads waiting on the state change are then scheduled to reenter the monitor.