ManualEvent (Variable type)

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Declaration
Using the ManualEvent variables

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ManualEvent (Variable type)

In french: SignalManuel

The ManualEvent type is used to manage a manual event. A manual event is used to simplify the synchronization between several threads.

A manual event can only be modified by EventChange.

Note: It is preferable to use a variable of type AutomaticEvent or ManualEvent variable to create a signal, rather than naming it using a string. Indeed, using a variable allows you to:

manage the variable scope,
avoid having 2 events with the same name in 2 different threads.

Example

// THREAD PRINCIPAL
//------------------
// Définition du signal
s is ManualEvent
// Lancement du thread
ThreadExecute("Thread", threadNormal, ProcThread, s)
// Code en parallèle du thread
...
// On attend le signal déclenché par le thread
EventWait(s)

// THREAD SECONDAIRE
// ----------------------
PROCEDURE ProcThread(s)

// Code dans le thread
...
// Débloque le thread principal
EventOpen(s)

Declaration

Declaring a manual event (simple syntax) Hide the details

MyVariable is ManualEvent

In this case, the manual event is closed when it is created.

Declaring a manual event (advanced syntax) Hide the details

MyVariable is ManualEvent(<Initial status>)

<Initial status>: Integer constant

Initial status of the event:
eventOpen The event is open when it is created.
eventClose The event is closed when it is created.

Remarks

Using the ManualEvent variables

The ManualEvent variables can be used to synchronize threads in the functions:

standard syntax:


EventClose	Closes a synchronization event between several threads.
EventOpen	Opens a synchronization event between several threads.
EventWait	Locks the current thread while waiting for the specified event to be opened.

prefix syntax:


<ManualEvent variable>.Close	Closes a synchronization event between several threads.
<ManualEvent variable>.Open	Opens a synchronization event between several threads.
<ManualEvent variable>.Wait	Locks the current thread while waiting for the specified event to be opened.

When calling the EventOpen (or <ManualEvent variable>.Open) function, the signal remains open:

all the pending threads are freed,
all the threads that will reach the event later will go through without waiting.

When calling the EventClose (or <ManualEvent variable>.Close) function, the signal is closed: all threads reaching the signal remain blocked.