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OSUnlock

Function : OS Memory
OSUnlock - Unlock a Domino memory object.

#include <osmem.h>
BOOL LNPUBLIC OSUnlock(

    HANDLE  handle);
Description :

OSUnlock is called to indicate that an application no longer needs physical access to the specified object. The lock count on the object is then decremented, and the calling application must then assume that the physical address for that object is no longer valid. An object must be fully unlocked (reference count = 0) before it can be deallocated with OSMemFree.

It is recommended that once an application is temporarily done using a memory object, it unlock the handle associated with that object, allowing the object to be moved by the memory manager. This will prevent the creation of "islands" that prevent efficient allocation/reallocation of memory. Islands lead to poor performance or insufficient memory errors. When you require a real address, just call OSLockObject and a new pointer value will be returned.

Most APIs that require a handle as an argument, require that the handle be unlocked.

An application can lock the same object more than once -- a lock reference count is maintained. It is not actually moveable until all locks are released (reference count = 0).

Calling this routine with a HANDLE that is invalid or out of range will result in a Notes PANIC halt .

Note - this routine is implemented as a macro that just calls OSUnlockObject with the same argument. It is provided merely to facilitate symmetry with OSLock:

define OSUnlock(handle) OSUnlockObject(handle)

Parameters : Input : handle - Handle for the object to be unlocked.

Output : (routine) - Always returns TRUE. There is no need to check the return value.

Sample Usage :

   /* Cleanup memory */

   if (wCleanUp & UNLOCK_HCDBUF)
       OSUnlock(hCDBuf);
See Also : OSLock OSUnlockBlock OSUnlockObject