## NAME

ACE_Process_Mutex - A wrapper for mutexes that can be used across processes on the same host machine, as well as within a process, of course.

## SYNOPSIS

    #include <ace/Synch.h>

    class ACE_Process_Mutex
    {
      public:
        ACE_Process_Mutex (LPCTSTR name = 0, void *arg = 0);
        ~ACE_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_mutex_t &lock (void) const;
        void dump (void) const;
        ACE_ALLOC_HOOK_DECLARE;
      private:
        ACE_Mutex lock_;
        TCHAR name_[ACE_UNIQUE_NAME_LEN];
        LPCTSTR unique_name (void);
        ACE_SV_Semaphore_Complex lock_;
    };

## DESCRIPTION

Wrappers for various synchronization routines.

## PUBLIC MEMBERS

    ACE_Process_Mutex (LPCTSTR name = 0, void *arg = 0);

Create a Process_Mutex, passing in the optional `name`.

    ~ACE_Process_Mutex (void);

    int remove (void);

Explicitly destroy the mutex.

    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_mutex_t &lock (void) const;

Return the underlying mutex.

    void dump (void) const;

Dump the state of an object.

    ACE_ALLOC_HOOK_DECLARE;

Declare the dynamic allocation hooks.

## PRIVATE MEMBERS

    ACE_Mutex lock_;

    TCHAR name_[ACE_UNIQUE_NAME_LEN];

If the user does not provide a name we generate a unique name in this buffer.

    LPCTSTR unique_name (void);

Create and return the unique name.

    ACE_SV_Semaphore_Complex lock_;

We need this to get the right semantics...

## AUTHOR

Doug Schmidt

## LIBRARY

ace