A semaphore allows for protection of a resource that can be accessed by a fixed number of simultaneous threads. More...

#include <FXSemaphore.h>

Public Member Functions
	FXSemaphore (FXint count=1)
	Initialize semaphore with given count.

FXbool	wait ()
	Decrement semaphore by 1, waiting if count is zero. More...

FXbool	wait (FXTime nsec)
	Try decrement semaphore; return true if successful. More...

FXbool	trywait ()
	Try decrement semaphore, and return true if successful. More...

FXbool	post ()
	Increment semaphore by 1. More...

	~FXSemaphore ()
	Delete semaphore.

Detailed Description

A semaphore allows for protection of a resource that can be accessed by a fixed number of simultaneous threads.

A typical example of the use of semaphores is for a buffer containing N items. A producer thread may freely append N items before blocking for space to become available; a consumer thread can remove items and block only when no items are left. Thus, two counting semaphores could be used to manage such a buffer, one counting empty slots and one counting filled slots. As long as production and consumption proceed at comparable rates, no thread needs to be suspended.

Member Function Documentation

◆ post()

FXbool FX::FXSemaphore::post ( )

Increment semaphore by 1.

Return false if an error occurred.

◆ trywait()

FXbool FX::FXSemaphore::trywait ( )

Try decrement semaphore, and return true if successful.

Return false if count was zero or if an error occurred.

◆ wait() [1/2]

FXbool FX::FXSemaphore::wait ( )

Decrement semaphore by 1, waiting if count is zero.

Return false if an error occurred.

◆ wait() [2/2]

FXbool FX::FXSemaphore::wait ( FXTime nsec )

Try decrement semaphore; return true if successful.

Return false if timed out or an error occurred.

The documentation for this class was generated from the following file: