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4/8/2010

This function releases ownership of the specified mutex object.

Syntax 

BOOL ReleaseMutex(
  HANDLE 
hMutex
);

Parameters

hMutex

[in] Handle to the mutex object. The CreateMutexfunction returns this handle.

Return Value

Nonzero indicates success. Zero indicates failure. To get extended error information, call GetLastError.

Remarks

The ReleaseMutexfunction fails if the calling thread does not own the mutex object.

A thread gets ownership of a mutex by specifying a handle to the mutex in one of the wait functions. The thread that creates a mutex object can also get immediate ownership without using one of the wait functions. When the owning thread no longer needs to own the mutex object, it calls the ReleaseMutexfunction.

While a thread has ownership of a mutex, it can specify the same mutex in additional wait-function calls without blocking its execution. This prevents a thread from deadlocking itself while waiting for a mutex that it already owns. However, to release its ownership, the thread must call ReleaseMutexonce for each time that the mutex satisfied a wait function call.

Each object type, such as memory maps, semaphores, events, message queues, mutexes, and watchdog timers, has its own separate namespace. Empty strings, "", are handled as named objects. On Windows desktop-based platforms, synchronization objects all share the same namespace.

Requirements

Header winbase.h
Library Nk.lib
Windows Embedded CE Windows CE 1.01 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also