IStream::UnlockRegion (Compact 2013)

3/26/2014

This method removes the access restriction on a range of bytes previously restricted with IStream::LockRegion.

Syntax

HRESULT UnlockRegion( 
  ULARGE_INTEGER libOffset, 
  ULARGE_INTEGER cb, 
  DWORD dwLockType 
);

Parameters

• libOffset
  [in] Byte offset for the beginning of the range.

• cb
  [in] Length, in bytes,of the range to be restricted.

• dwLockType
  [in] Access restrictions previously placed on the range.

Return Value

The following table shows the return values for this method.

Value	Description
S_OK	The byte range was unlocked.
E_PENDING	Asynchronous Storage only: Part or all of the stream's data is currently unavailable.
STG_E_INVALIDFUNCTION	Locking is not supported at all or the specific type of lock requested is not supported.
STG_E_LOCKVIOLATION	The requested unlock cannot be granted.
STG_E_REVERTED	The object has been invalidated by a revert operation above it in the transaction tree.

Remarks

IStream::UnlockRegion unlocks a region previously locked with the IStream::LockRegion method. Locked regions must later be explicitly unlocked by calling IStream::UnlockRegion with exactly the same values for the libOffset, cb, and dwLockType parameters.

The region must be unlocked before the stream is released.

Two adjacent regions cannot be locked separately and then unlocked with a single unlock call.

To determine whether the platform supports this interface, see Determining Supported COM APIs.

Requirements

Header	objidl.h, objidl.idl
Library	ole32.lib, uuid.lib

See Also

Reference

IStream