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diff --git a/ACE/ace/Process_Mutex.h b/ACE/ace/Process_Mutex.h
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+// -*- C++ -*-
+
+//=============================================================================
+/**
+ *  @file    Process_Mutex.h
+ *
+ *  $Id$
+ *
+ *   A wrapper for mutexes that can be used across processes on the
+ *   same host machine, as well as within a process, of course.
+ *
+ * @author Douglas C. Schmidt <schmidt@uci.edu>
+ */
+//=============================================================================
+
+#ifndef ACE_PROCESS_MUTEX_H
+#define ACE_PROCESS_MUTEX_H
+
+#include /**/ "ace/pre.h"
+
+#include "ace/config-all.h"
+
+#if !defined (ACE_LACKS_PRAGMA_ONCE)
+# pragma once
+#endif /* ACE_LACKS_PRAGMA_ONCE */
+
+// To make it easier to carry the setting though this file as well as
+// Process_Mutex.{cpp inl}, set a private macro here.
+#ifdef _ACE_USE_SV_SEM
+#  undef _ACE_USE_SV_SEM
+#endif /* _ACE_USE_SV_SEM */
+
+#if defined (ACE_HAS_SYSV_IPC) && !defined (ACE_USES_MUTEX_FOR_PROCESS_MUTEX)
+#  include "ace/SV_Semaphore_Complex.h"
+#  define _ACE_USE_SV_SEM
+#else
+#  include "ace/Mutex.h"
+#endif /* ACE_HAS_SYSV_IPC && !ACE_USES_MUTEX_FOR_PROCESS_MUTEX */
+
+ACE_BEGIN_VERSIONED_NAMESPACE_DECL
+
+// Forward declarations
+class ACE_Time_Value;
+
+/**
+ * @class ACE_Process_Mutex
+ *
+ * @brief A wrapper for mutexes that can be used across processes on
+ * the same host machine, as well as within a process, of
+ * course.
+ *
+ * @attention The mechanism upon which @c ACE_Process_Mutex is based
+ * can be configured at build time to be either @c ACE_SV_Semaphore_Complex
+ * (on platforms that support it) or @c ACE_Mutex. On platforms that
+ * require interprocess mutexes be allocated from shared memory (Pthreads
+ * and UI Threads are examples), @c ACE_SV_Semaphore_Complex provides a
+ * more reliable mechanism for implementing inter-process mutex than
+ * @c ACE_Mutex. However, at least on some platforms,
+ * @c ACE_SV_Semaphore_Complex is limited to a small number of
+ * objects by the underlying System V IPC kernel parameters. If you
+ * want to force use of @c ACE_Mutex as the underlying mechanism, set
+ * @c ACE_USES_MUTEX_FOR_PROCESS_MUTEX in your @c config.h file.
+ * Also, if you require the ability to do a timed @c acquire(), you must
+ * set @c ACE_USES_MUTEX_FOR_PROCESS_MUTEX, as timed acquire does not
+ * work with System V semaphores.
+ * @attention Currently there is also the operational difference between
+ * pthreads and semaphores based @c. For semaphore base @c the semaphore
+ * is destroyed after the last instance of @c in OS. In contrary, pthread based
+ * @c is destroyed when the owner, namely the process which created the
+ * first instance of @c destroys the mutex. For protable applications it is better
+ * to always ensure that the owner of the mutex destroys it after the
+ * other processes.
+ */
+class ACE_Export ACE_Process_Mutex
+{
+public:
+  /**
+   * Create a Process_Mutex, passing in the optional @c name.
+   *
+   * @param name optional, null-terminated string containing the name of
+   * the object. Multiple users of the same @c ACE_Process_Mutex must use
+   * the same name to access the same object.  If not specified, a name
+   * is generated.
+   * @param arg optional, attributes to be used to initialize the mutex.
+   * If using @c ACE_SV_Semaphore_Complex as the underlying mechanism,
+   * this argument is ignored.
+   * @param mode optional, the protection mode for either the backing store
+   * file (for ACE_Mutex use) or the ACE_SV_Semaphore_Complex that's created.
+   */
+  ACE_Process_Mutex (const char *name = 0,
+                     void *arg = 0,
+                     mode_t mode = ACE_DEFAULT_FILE_PERMS);
+
+#if defined (ACE_HAS_WCHAR)
+  /**
+   * Create a Process_Mutex, passing in the optional @c name. (@c wchar_t
+   * version)
+   *
+   * @param name optional, null-terminated string containing the name of
+   * the object. Multiple users of the same @c ACE_Process_Mutex must use
+   * the same name to access the same object. If not specified, a name
+   * is generated.
+   * @param arg optional, attributes to be used to initialize the mutex.
+   * If using @c ACE_SV_Semaphore_Complex as the underlying mechanism,
+   * this argument is ignored.
+   * @param mode optional, the protection mode for either the backing store
+   * file (for ACE_Mutex use) or the ACE_SV_Semaphore_Complex that's created.
+   */
+  ACE_Process_Mutex (const wchar_t *name,
+                     void *arg = 0,
+                     mode_t mode = ACE_DEFAULT_FILE_PERMS);
+#endif /* ACE_HAS_WCHAR */
+
+  ~ACE_Process_Mutex (void);
+
+  /**
+   * Explicitly destroy the mutex.  Note that only one thread should
+   * call this method since it doesn't protect against race
+   * conditions.
+   *
+   * @return 0 on success; -1 on failure.
+   */
+  int remove (void);
+
+  /**
+   * Acquire lock ownership (wait on queue if necessary).
+   *
+   * @return 0 on success; -1 on failure.
+   */
+  int acquire (void);
+
+  /**
+   * Acquire lock ownership, but timeout if lock if hasn't been
+   * acquired by given time.
+   *
+   * @param tv the absolute time until which the caller is willing to
+   * wait to acquire the lock.
+   *
+   * @return 0 on success; -1 on failure.
+   */
+  int acquire (ACE_Time_Value &tv);
+
+  /**
+   * Conditionally acquire lock (i.e., don't wait on queue).
+   *
+   * @return 0 on success; -1 on failure.  If the lock could not be acquired
+   * because someone else already had the lock, @c errno is set to @c EBUSY.
+   */
+  int tryacquire (void);
+
+  /// Release lock and unblock a thread at head of queue.
+  int release (void);
+
+  /// Acquire lock ownership (wait on queue if necessary).
+  int acquire_read (void);
+
+  /// Acquire lock ownership (wait on queue if necessary).
+  int acquire_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>.
+   */
+  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);
+
+  /**
+   * This is only here for consistency with the other synchronization
+   * APIs and usability with Lock adapters. Assumes the caller already has
+   * acquired the mutex and returns 0 in all cases.
+   */
+  int tryacquire_write_upgrade (void);
+
+#if !defined (_ACE_USE_SV_SEM)
+  /// Return the underlying mutex.
+  const ACE_mutex_t &lock (void) const;
+#endif /* !_ACE_USE_SV_SEM */
+
+  /// Dump the state of an object.
+  void dump (void) const;
+
+  /// Declare the dynamic allocation hooks.
+  ACE_ALLOC_HOOK_DECLARE;
+
+private:
+  /// If the user does not provide a name we generate a unique name in
+  /// this buffer.
+  ACE_TCHAR name_[ACE_UNIQUE_NAME_LEN];
+
+  /// Create and return the unique name.
+  const ACE_TCHAR *unique_name (void);
+
+#if defined (_ACE_USE_SV_SEM)
+  /// We need this to get the right semantics...
+  ACE_SV_Semaphore_Complex lock_;
+#else
+  ACE_Mutex lock_;
+#endif /* _ACE_USE_SV_SEM */
+};
+
+ACE_END_VERSIONED_NAMESPACE_DECL
+
+#if defined (__ACE_INLINE__)
+#include "ace/Process_Mutex.inl"
+#endif /* __ACE_INLINE__ */
+
+#include /**/ "ace/post.h"
+
+#endif /* ACE_PROCESS_MUTEX_H */