ACE_Null_Semaphore Class Reference

Implement a do nothing ACE_Semaphore, i.e., all the methods are no ops. More...

#include <Null_Semaphore.h>

List of all members.

Public Member Functions
	ACE_Null_Semaphore (unsigned int=1, int=0, const ACE_TCHAR *=0, void *=0, int=0x7fffffff)
	~ACE_Null_Semaphore (void)
int	remove (void)
	Return 0.
int	acquire (void)
	Return 0.
int	acquire (ACE_Time_Value &)
	Return -1 with == .
int	acquire (ACE_Time_Value *)
	Return -1 with == .
int	tryacquire (void)
	Return 0.
int	release (void)
	Return 0.
int	release (size_t)
	Return 0.
int	acquire_write (void)
	Return 0.
int	tryacquire_write (void)
	Return 0.
int	tryacquire_write_upgrade (void)
	Return 0.
int	acquire_read (void)
	Return 0.
int	tryacquire_read (void)
	Return 0.
void	dump (void) const
	Dump the state of an object.

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Detailed Description

Implement a do nothing ACE_Semaphore, i.e., all the methods are no ops.

Although the methods are no-ops, the return values are different for the blocking as opposed to timed acquires. The blocking version of acquire() is often used to serialize access to a critical section, whereas the timed version is often used to wait for another thread to update some condition or change some shared state. When using an ACE_Null_Semaphore, however, there's no other thread involved to change a state or condition (otherwise, a null semaphore would be inappropriate). Returning an error value signifies that the state or condition has not been (and can't be) changed, which is consistent with the behavior of the threaded case where a timeout occurs before the state or condition is changed.

Definition at line 49 of file Null_Semaphore.h.

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Constructor & Destructor Documentation

ACE_Null_Semaphore::ACE_Null_Semaphore (  unsigned  int = 1, int  = 0, const ACE_TCHAR *  = 0, void *  = 0, int  = 0x7fffffff )  [inline]

Definition at line 52 of file Null_Semaphore.h. References ACE_TCHAR. {}

ACE_Null_Semaphore::~ACE_Null_Semaphore (  void   )  [inline]

Definition at line 57 of file Null_Semaphore.h. {}

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Member Function Documentation

int ACE_Null_Semaphore::acquire (  ACE_Time_Value *   )  [inline]

Return -1 with == . Definition at line 68 of file Null_Semaphore.h. References ETIME. {errno = ETIME; return -1;}

int ACE_Null_Semaphore::acquire (  ACE_Time_Value &   )  [inline]

Return -1 with == . Definition at line 65 of file Null_Semaphore.h. References ETIME. {errno = ETIME; return -1;}

int ACE_Null_Semaphore::acquire (  void   )  [inline]

Return 0. Definition at line 62 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::acquire_read (  void   )  [inline]

Return 0. Definition at line 89 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::acquire_write (  void   )  [inline]

Return 0. Definition at line 80 of file Null_Semaphore.h. {return 0;}

void ACE_Null_Semaphore::dump (  void   )  const [inline]

Dump the state of an object. Definition at line 95 of file Null_Semaphore.h. {}

int ACE_Null_Semaphore::release (  size_t   )  [inline]

Return 0. Definition at line 77 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::release (  void   )  [inline]

Return 0. Definition at line 74 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::remove (  void   )  [inline]

Return 0. Definition at line 59 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::tryacquire (  void   )  [inline]

Return 0. Definition at line 71 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::tryacquire_read (  void   )  [inline]

Return 0. Definition at line 92 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::tryacquire_write (  void   )  [inline]

Return 0. Definition at line 83 of file Null_Semaphore.h. {return 0;}

int ACE_Null_Semaphore::tryacquire_write_upgrade (  void   )  [inline]

Return 0. Definition at line 86 of file Null_Semaphore.h. {return 0;}

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

• Null_Semaphore.h

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