gecko-dev/docs/nspr/reference/pr_notifycondvar.rst

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PR_NotifyCondVar
================
Notifies a condition variable of a change in its associated monitored
data.
Syntax
------
.. code:: eval
#include <prcvar.h>
PRStatus PR_NotifyCondVar(PRCondVar *cvar);
Parameter
~~~~~~~~~
:ref:`PR_NotifyCondVar` has one parameter:
``cvar``
The condition variable to notify.
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.
Notification of a condition variable signals a change of state in some
monitored data. When the notification occurs, the runtime promotes a
thread that is waiting on the condition variable to a ready state. If
more than one thread is waiting, the selection of which thread gets
promoted cannot be predicted. This implies that all threads waiting on a
single condition variable must have the same semantics. If no thread is
waiting on the condition variable, the notify operation is a no-op.