PTimedMutex Class Reference

This class defines a thread mutual exclusion object. More...

#include <mutex.h>

Inheritance diagram for PTimedMutex:

Collaboration diagram for PTimedMutex:

Public Member Functions
	PTimedMutex ()
	PTimedMutex (const PTimedMutex &mutex)
	Copy constructor is allowed but does not copy, allocating a new mutex. More...
PTimedMutex &	operator= (const PTimedMutex &)
	Assignment operator is allowed but does nothing. More...
virtual void	Wait ()
	Block until the synchronisation object is available. More...
virtual PBoolean	Wait (const PTimeInterval &timeout)
	Block, for a time, until the synchronisation object is available. More...
virtual void	Signal ()
	Signal that the synchronisation object is available. More...
PINLINE bool	Try ()
	Try to enter the critical section for exlusive access. More...
Public Member Functions inherited from PSync
	PSync ()
Public Member Functions inherited from PObject
unsigned	GetTraceContextIdentifier () const
	Get PTRACE context identifier. More...
void	SetTraceContextIdentifier (unsigned id)
void	GetTraceContextIdentifier (PObject &obj)
void	GetTraceContextIdentifier (PObject *obj)
void	SetTraceContextIdentifier (const PObject &obj)
void	SetTraceContextIdentifier (const PObject *obj)
virtual	~PObject ()
virtual PObject *	Clone () const
	Create a copy of the class on the heap. More...
template<class CLS >
CLS *	CloneAs () const
	As for Clone() but converts to specified type. More...
virtual PINDEX	HashFunction () const
	This function yields a hash value required by the PDictionary class. More...
virtual const char *	GetClass (unsigned ancestor=0) const
	Get the current dynamic type of the object instance. More...
PBoolean	IsClass (const char *cls) const
virtual PBoolean	InternalIsDescendant (const char *clsName) const
	Determine if the dynamic type of the current instance is a descendent of the specified class. More...
__inline const PObject *	PTraceObjectInstance () const
virtual Comparison	Compare (const PObject &obj) const
	Compare the two objects and return their relative rank. More...
virtual Comparison	CompareObjectMemoryDirect (const PObject &obj) const
	Determine the byte wise comparison of two objects. More...
bool	operator== (const PObject &obj) const
	Compare the two objects. More...
bool	operator!= (const PObject &obj) const
	Compare the two objects. More...
bool	operator< (const PObject &obj) const
	Compare the two objects. More...
bool	operator> (const PObject &obj) const
	Compare the two objects. More...
bool	operator<= (const PObject &obj) const
	Compare the two objects. More...
bool	operator>= (const PObject &obj) const
	Compare the two objects. More...
virtual void	PrintOn (ostream &strm) const
	Output the contents of the object to the stream. More...
virtual void	ReadFrom (istream &strm)
	Input the contents of the object from the stream. More...

Additional Inherited Members
Public Types inherited from PObject
enum	Comparison { LessThan = -1, EqualTo = 0, GreaterThan = 1 }
	Result of the comparison operation performed by the Compare() function. More...
Static Public Member Functions inherited from PObject
static const char *	Class ()
	Get the name of the class as a C string. More...
static __inline const PObject *	PTraceObjectInstance (const char *)
static __inline const PObject *	PTraceObjectInstance (const PObject *obj)
static Comparison	InternalCompareObjectMemoryDirect (const PObject *obj1, const PObject *obj2, PINDEX size)
	Internal function caled from CompareObjectMemoryDirect() More...
Protected Member Functions inherited from PObject
	PObject ()
	Constructor for PObject, made protected so cannot ever create one on its own. More...
Protected Attributes inherited from PObject
unsigned	m_traceContextIdentifier
Friends inherited from PObject

Detailed Description

This class defines a thread mutual exclusion object.

A mutex is where a piece of code or data cannot be accessed by more than one thread at a time. To prevent this the PMutex is used in the following manner:

      PMutex mutex;

      ...

      mutex.Wait();

      ... critical section - only one thread at a time here.

      mutex.Signal();

      ...

The first thread will pass through the Wait() function, a second thread will block on that function until the first calls the Signal() function, releasing the second thread.

Constructor & Destructor Documentation

PTimedMutex::PTimedMutex

(

)

PTimedMutex::PTimedMutex

(

const PTimedMutex &

mutex

)

Copy constructor is allowed but does not copy, allocating a new mutex.

Two copies of the same mutex information would be very bad.

Member Function Documentation

PTimedMutex& PTimedMutex::operator= ( const PTimedMutex &  )

inline

Assignment operator is allowed but does nothing.

Overwriting the old mutex information would be very bad.

virtual void PTimedMutex::Signal ( )

virtual

Signal that the synchronisation object is available.

Implements PSync.

PINLINE bool PTimedMutex::Try ( )

inline

Try to enter the critical section for exlusive access.

Does not wait.

Returns

true if cirical section entered, leave/Signal must be called.

References Wait().

virtual void PTimedMutex::Wait ( )

virtual

Block until the synchronisation object is available.

Implements PSync.

Referenced by Try().

virtual PBoolean PTimedMutex::Wait ( const PTimeInterval &  timeout )

virtual

Block, for a time, until the synchronisation object is available.

Returns

true if lock is acquired, false if timed out

Implements PSync.

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

• mutex.h