itk::ConditionVariable Class Reference

A thread synchronization object used to suspend execution until some condition on shared data is met. More...

#include <itkConditionVariable.h>

Inheritance diagram for itk::ConditionVariable:

[legend]Collaboration diagram for itk::ConditionVariable:

[legend]List of all members.

Public Types
typedef ConditionVariable	Self
typedef LightObject	Superclass
typedef SmartPointer< Self >	Pointer
typedef SmartPointer< const Self >	ConstPointer
Public Member Functions
virtual const char *	GetNameOfClass () const
void	Wait (SimpleMutexLock *mutex)
void	Signal ()
void	Broadcast ()
Static Public Member Functions
Pointer	New ()
Protected Member Functions
	ConditionVariable ()
	~ConditionVariable ()

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Detailed Description

A thread synchronization object used to suspend execution until some condition on shared data is met.

A thread calls Wait() to suspend its execution until the condition is met. Each call to Signal() from an executing thread will then cause a single waiting thread to be released. A call to Signal() means, "signal that the condition is true." Broadcast() releases all threads waiting on the condition variable.

The ITK ConditionVariable implementation is consistent with the standard definition and use of condition variables in pthreads and other common thread libraries.

IMPORTANT: A condition variable always requires an associated SimpleMutexLock object. The mutex object is used to avoid a dangerous race condition when Wait() and Signal() are called simultaneously from two different threads.

On systems using pthreads, this implementation abstract the standard calls to the pthread condition variable. On Win32 systems, there is no system provided condition variable. This class implements a condition variable using a critical section, a semphore, an event and a number of counters. The implementation is almost an extract translation of the implementation presented by Douglas C Schmidt and Irfan Pyarali in "Strategies for Implementing POSIX Condition Variables on Win32". This article can be found at http://www.cs.wustl.edu/~schmidt/win32-cv-1.html

Definition at line 67 of file itkConditionVariable.h.

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Member Typedef Documentation

typedef SmartPointer<const Self> itk::ConditionVariable::ConstPointer

Reimplemented from itk::LightObject. Definition at line 74 of file itkConditionVariable.h.

typedef SmartPointer<Self> itk::ConditionVariable::Pointer

Reimplemented from itk::LightObject. Definition at line 73 of file itkConditionVariable.h.

typedef ConditionVariable itk::ConditionVariable::Self

Standard class typedefs. Reimplemented from itk::LightObject. Definition at line 71 of file itkConditionVariable.h.

typedef LightObject itk::ConditionVariable::Superclass

Definition at line 72 of file itkConditionVariable.h.

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Constructor & Destructor Documentation

itk::ConditionVariable::ConditionVariable (   )  [protected]

itk::ConditionVariable::~ConditionVariable (   )  [protected]

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Member Function Documentation

void itk::ConditionVariable::Broadcast (   )

Signal that the condition is true and release all waiting threads

virtual const char* itk::ConditionVariable::GetNameOfClass (   )  const [virtual]

Run-time type information (and related methods). Reimplemented from itk::LightObject.

Pointer itk::ConditionVariable::New (   )  [static]

Method for creation through the object factory. Reimplemented from itk::LightObject.

void itk::ConditionVariable::Signal (   )

Signal that the condition is true and release one waiting thread

void itk::ConditionVariable::Wait (  SimpleMutexLock *  mutex  )

Suspend execution of this thread until the condition is signaled. The argument is a SimpleMutex object that must be locked prior to calling this method.

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

• itkConditionVariable.h

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