EventChange (Function)

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Summary table about the operating mode of event

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EventChange (Function)

In french: SignalModifie

Modifies the status of an event.

Example

// Création d'un signal
EventCreate("Allez-y", eventManual, eventClose)
// Exécution d'un premier thread
ThreadExecute("Thread1", threadNormal, "Thread_Premier")
// Bloque le thread en cours jusqu'à l'obtention du signal
ThreadWaitSignal()

// Exécution d'un second thread
ThreadExecute("Thread2", threadNormal, "Thread_Second")
// Bloque le thread en cours jusqu'à l'obtention du signal
ThreadWaitSignal()

// Modifie le signal pour exécuter les threads
EventChange("Allez-y", eventOpen)

//----------------------------------------------
PROCEDURE Thread_Premier()
Trace(dbgInfo(dbgProcess) + " - ThreadEnvoieSignal(threadPrincipal)")
ThreadSendSignal(threadMain)
EventWait("Allez-y")
Trace(dbgInfo(dbgProcess) + " - Signal reçu")

//--------------------------------------------
PROCEDURE Thread_Second()
Trace(dbgInfo(dbgProcess) + " - ThreadEnvoieSignal(threadPrincipal)")
ThreadSendSignal(threadMain)
EventWait("Allez-y")
Trace(dbgInfo(dbgProcess) + " - Signal reçu")

Syntax

EventChange(<Event> [, <New status>])

<Event>: Character string

Name of the event to modify. If this event does not exist, it is automatically created with the default options (automatic mode) and in the specified status.

<New status>: Optional constant

Status of the event:
eventClose Closes the event.
This constant is equivalent to EventClose.
eventOpen
(Default value) Opens the event. If threads are waiting for the event, they are automatically unlocked.
This constant is equivalent to EventOpen.
eventOpenAndClose Opens the event, unlocks all the pending threads and closes the event. This constant is not recommended. It is kept for backward compatibility.

Remarks

Summary table about the operating mode of event

Value of EventChange	Automatic event (by default)	Manual event

eventOpen	A single thread is processed by the event. The event is automatically closed once the thread is processed. Waiting threads If no thread was waiting, the signal remains open until the next thread passes, then closes again. New threads If more threads arrive, they are put on hold.	The event is opened. Waiting threads: All waiting threads pass through. New threads: If other threads arrive while the signal is still open, they pass.
eventOpenAndClose This constant is not recommended. It is kept for backward compatibility.	A single thread is processed by the event. The event is automatically closed once the thread is processed. Waiting threads If no thread is waiting, the signal remains closed. New threads If more threads arrive, they are put on hold.	All the threads are processed by the event. The event is automatically closed once all the threads are processed. New threads If more threads arrive, they are put on hold.
eventClose	The event remains closed. New threads If more threads arrive, they are put on hold.	The event is closed. New threads If more threads arrive, they are put on hold.

Component: wd300vm.dll