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ACE_Process_Semaphore Class Reference

Wrapper for Dijkstra style general semaphores that work across processes. More...

#include <Process_Semaphore.h>

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List of all members.

Public Methods

 ACE_Process_Semaphore (u_int count=1, const ACE_TCHAR *name=0, void *=0, int max=0x7FFFFFFF)
 Initialize the semaphore, with an initial value of <count> and a maximum value of <max>. More...

 ~ACE_Process_Semaphore (void)
 This method is a no-op, i.e., it doesn't remove the semaphore. More...

int remove (void)
 Explicitly destroy the semaphore. More...

int acquire (void)
 Block the thread until the semaphore count becomes greater than 0, then decrement it. More...

int tryacquire (void)
 Conditionally decrement the semaphore if count is greater than 0 (i.e., won't block). More...

int release (void)
 Increment the semaphore, potentially unblocking a waiting thread. More...

int acquire_read (void)
 Acquire semaphore ownership. More...

int acquire_write (void)
 Acquire semaphore ownership. More...

int tryacquire_read (void)
 Conditionally acquire semaphore (i.e., won't block). More...

int tryacquire_write (void)
 Conditionally acquire semaphore (i.e., won't block). More...

int tryacquire_write_upgrade (void)
 This is only here to make the <ACE_Process_Semaphore> interface consistent with the other synchronization APIs. More...

const ACE_sema_t & lock (void) const
 Return the underlying lock. More...

void dump (void) const
 Dump the state of an object. More...


Public Attributes

 ACE_ALLOC_HOOK_DECLARE
 Declare the dynamic allocation hooks. More...


Protected Attributes

ACE_Semaphore lock_

Detailed Description

Wrapper for Dijkstra style general semaphores that work across processes.


Constructor & Destructor Documentation

ACE_Process_Semaphore::ACE_Process_Semaphore u_int    count = 1,
const ACE_TCHAR   name = 0,
void *    arg = 0,
int    max = 0x7FFFFFFF
 

Initialize the semaphore, with an initial value of <count> and a maximum value of <max>.

ACE_Process_Semaphore::~ACE_Process_Semaphore void   
 

This method is a no-op, i.e., it doesn't remove the semaphore.

If you want to remove the semaphore, you must call the <remove> method explicitly.


Member Function Documentation

int ACE_Process_Semaphore::acquire void   
 

Block the thread until the semaphore count becomes greater than 0, then decrement it.

ACE_INLINE int ACE_Process_Semaphore::acquire_read void   
 

Acquire semaphore ownership.

This calls <acquire> and is only here to make the <ACE_Process_Semaphore> interface consistent with the other synchronization APIs.

ACE_INLINE int ACE_Process_Semaphore::acquire_write void   
 

Acquire semaphore ownership.

This calls <acquire> and is only here to make the <ACE_Process_Semaphore> interface consistent with the other synchronization APIs.

void ACE_Process_Semaphore::dump void    const
 

Dump the state of an object.

const ACE_sema_t& ACE_Process_Semaphore::lock void    const
 

Return the underlying lock.

int ACE_Process_Semaphore::release void   
 

Increment the semaphore, potentially unblocking a waiting thread.

int ACE_Process_Semaphore::remove void   
 

Explicitly destroy the semaphore.

Note that only one thread should call this method since it doesn't protect against race conditions.

int ACE_Process_Semaphore::tryacquire void   
 

Conditionally decrement the semaphore if count is greater than 0 (i.e., won't block).

Returns -1 on failure. If we "failed" because someone else already had the lock, <errno> is set to <EBUSY>.

ACE_INLINE int ACE_Process_Semaphore::tryacquire_read void   
 

Conditionally acquire semaphore (i.e., won't block).

This calls <tryacquire> and is only here to make the <ACE_Process_Semaphore> interface consistent with the other synchronization APIs. Returns -1 on failure. If we "failed" because someone else already had the lock, <errno> is set to <EBUSY>.

ACE_INLINE int ACE_Process_Semaphore::tryacquire_write void   
 

Conditionally acquire semaphore (i.e., won't block).

This calls <tryacquire> and is only here to make the <ACE_Process_Semaphore> interface consistent with the other synchronization APIs. Returns -1 on failure. If we "failed" because someone else already had the lock, <errno> is set to <EBUSY>.

ACE_INLINE int ACE_Process_Semaphore::tryacquire_write_upgrade void   
 

This is only here to make the <ACE_Process_Semaphore> interface consistent with the other synchronization APIs.

Assumes the caller has already acquired the semaphore using one of the above calls, and returns 0 (success) always.


Member Data Documentation

ACE_Process_Semaphore::ACE_ALLOC_HOOK_DECLARE
 

Declare the dynamic allocation hooks.

ACE_Semaphore ACE_Process_Semaphore::lock_ [protected]
 


The documentation for this class was generated from the following files:
Generated on Tue Aug 20 15:26:21 2002 for ACE by doxygen1.2.13.1 written by Dimitri van Heesch, © 1997-2001