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Windows Embedded CE 6.0 R3


This function releases ownership of the specified critical section object.


void  LeaveCriticalSection(
  LPCRITICAL_SECTION lpCriticalSection


  • lpCriticalSection
    [in] Pointer to the critical section object.

Return Value



The threads of a single process can use a critical-section object for mutual-exclusion synchronization. The process is responsible for allocating the memory used by a critical-section object, which it can do by declaring a variable of type CRITICAL_SECTION. Before using a critical section, some thread of the process must call the InitializeCriticalSection function to initialize the object. A thread uses the EnterCriticalSection function to acquire ownership of a critical section object. To release its ownership, the thread must call LeaveCriticalSection once for each time that it entered the critical section.

If a thread calls LeaveCriticalSection when it does not have ownership of the specified critical section object, an error occurs that may cause another thread using EnterCriticalSection to wait indefinitely.

Any thread of the process can use the DeleteCriticalSection function to release the system resources that were allocated when the critical section object was initialized. After this function has been called, the critical section object can no longer be used for synchronization.

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.


Header winbase.h
Library Coremain.lib
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also


Synchronization Functions