PR_NotifyCondVar 编辑

Notifies a condition variable of a change in its associated monitored data.

Syntax

#include <prcvar.h>

/wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PRStatus PR_NotifyCondVar(/wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PRCondVar *cvar);

Parameter

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.