Test semaphore
Test semaphore ( semaphore ) : Boolean
| Parameter | Type | Description | |
|---|---|---|---|
| semaphore | Text | → | Name of the semaphore to test |
| Function result | Boolean | ← | True = the semaphore exists, False = the semaphore doesn’t exist |
Description
The Test semaphore command tests for the existence of a semaphore.
The difference between the Semaphore function and the Test semaphore function is that Test semaphore doesn’t create the semaphore if it doesn’t exist. If the semaphore exists, the function returns True. Otherwise, it returns False.
Example
The following example allows you to know the state of a process (in our case, while modifying the code) without modifying semaphore:
$Win:=Open window(x1;x2;y1;y2;-Palette window)
Repeat
If(Test semaphore("Encrypting code"))
POSITION MESSAGE($x3;$y3)
MESSAGE("Encrypting code being modified.")
Else
POSITION MESSAGE($x3;$y3)
MESSAGE("Modification of the encrypting code authorized.")
End if
Until(StopInfo)
CLOSE WINDOW
See also
Properties
| Command number | 652 |
| Thread safe | ✓ |