ACE_RW_Process_Mutex(3)

NAME

ACE_RW_Process_Mutex - Wrapper for readers/writer locks that exist across processes.

SYNOPSIS

#include <ace/Synch.h>
class ACE_RW_Process_Mutex
{
  public:
    ACE_RW_Process_Mutex (
        LPCTSTR name = 0,
        int flags = O_CREAT|O_RDWR
        );
    ~ACE_RW_Process_Mutex (void);
    int remove (void);
    int acquire (void);
    int tryacquire (void);
    int release (void);
    int acquire_read (void);
    int acquire_write (void);
    int tryacquire_read (void);
    int tryacquire_write (void);
    const ACE_File_Lock &lock (void) const;
    void dump (void) const;
    ACE_ALLOC_HOOK_DECLARE;
  private:
    ACE_File_Lock lock_;
};

DESCRIPTION

Wrappers for various synchronization routines.

PUBLIC MEMBERS

ACE_RW_Process_Mutex (LPCTSTR name = 0, int flags = O_CREAT|O_RDWR);

Create a readers/writer Process_Mutex, passing in the optional name.

~ACE_RW_Process_Mutex (void);

int remove (void);

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

int acquire (void);

Acquire lock ownership (wait on queue if necessary).

int tryacquire (void);

Conditionally acquire lock (i.e., don't wait on queue). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

int release (void);

Release lock and unblock a thread at head of queue.

int acquire_read (void);

Acquire lock ownership (wait on queue if necessary).

int acquire_write (void);

Acquire lock ownership (wait on queue if necessary).

int tryacquire_read (void);

Conditionally acquire a lock (i.e., won't block). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

int tryacquire_write (void);

Conditionally acquire a lock (i.e., won't block). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

const ACE_File_Lock &lock (void) const;

Return the underlying lock.

void dump (void) const;

Dump the state of an object.

ACE_ALLOC_HOOK_DECLARE;

Declare the dynamic allocation hooks.

PRIVATE MEMBERS

ACE_File_Lock lock_;

We need this to get the readers/writer semantics...

AUTHOR

Doug Schmidt

LIBRARY

ace