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Stored procedures
Locks the current thread until the semaphore is opened (which means until a "free" spot becomes available in the protected section).
Reminder: The semaphores are used to define a protected code section that can only be run by a specific number of threads.
Syntax
<Result> = SemaphoreStart(<Semaphore Name> [, <Maximum Time-out>])
<Result>: Boolean
  • True if the thread is allowed to enter in the code section,
  • False otherwise (maximum duration reached).
<Semaphore Name>: Character string (with quotes)
Name of semaphore to use. If the semaphore does not exist, it is created with the default options (see SemaphoreCreate)
<Maximum Time-out>: Optional integer or optional duration
Maximum time-out in hundredths of a second.
  • At the end of the specified duration, if the thread did not receive the authorization, <Result> is set to False.
  • If this parameter is not specified or if it corresponds to the Infinite constant, the wait is infinite.
  • If this parameter is set to 0, <Result> corresponds to the status of the semaphore. The thread is not pending.
This parameter can correspond to:
  • an integer corresponding to the number of hundredths of a second,
  • a Duration variable,
  • Versions 23 and later
    the direct indication of duration (1 s or 10 ms for example).
    New in version 23
    the direct indication of duration (1 s or 10 ms for example).
    the direct indication of duration (1 s or 10 ms for example).
Remarks

Equivalence

SemaphoreStart("SemaphoreName")
is equivalent to:
CriticalSectionStart("MyCriticalSection")
Indeed, by default, SemaphoreStart creates a semaphore limited to a single thread.
Component : wd250vm.dll
Minimum version required
  • Version 9
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