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Semaphore

Inherits: RefCounted < Object

A synchronization semaphore.

Description

A synchronization semaphore which can be used to synchronize multiple Threads. Initialized to zero on creation. Be careful to avoid deadlocks. For a binary version, see Mutex.

Tutorials

• Using multiple threads

Methods

void	post ( )
bool	try_wait ( )
void	wait ( )

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Method Descriptions

void post ( )

Lowers the Semaphore, allowing one more thread in.

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bool try_wait ( )

Like wait, but won't block, so if the value is zero, fails immediately and returns false. If non-zero, it returns true to report success.

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void wait ( )

Waits for the Semaphore, if its value is zero, blocks until non-zero.