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IVdsOpenVDisk::Merge method (vds.h)

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[Beginning with Windows 8 and Windows Server 2012, the Virtual Disk Service COM interface is superseded by the Windows Storage Management API.]

Merges a child virtual disk with its parents in the differencing chain.

Syntax

HRESULT Merge(
  [in]  MERGE_VIRTUAL_DISK_FLAG Flags,
  [in]  ULONG                   MergeDepth,
  [out] IVdsAsync               **ppAsync
);

Parameters

[in] Flags

A MERGE_VIRTUAL_DISK_FLAG enumeration value that specifies how the virtual disk is to be merged. Must be set to MERGE_VIRTUAL_DISK_FLAG_NONE.

[in] MergeDepth

The number of parent disks in the differencing chain to merge together. The disk must have been open with a ReadWriteDepth at least equal to this value.

[out] ppAsync

A pointer to an IVdsAsync interface that upon successful completion receives the IVdsAsync interface to monitor and control this operation. Callers must release the interface received when they have finished with it. If the IVdsAsync::Wait method is called on the interface and a success HRESULT value is returned, the interfaces returned in the VDS_ASYNC_OUTPUT structure must be released by calling the IUnknown::Release method on each interface pointer. However, if Wait returns a failure HRESULT value, or if the pHrResult parameter of Wait receives a failure HRESULT value, the interface pointers in the VDS_ASYNC_OUTPUT structure are NULL and do not need to be released. You can test for success or failure HRESULT values by using the SUCCEEDED and FAILED macros defined in Winerror.h.

Return value

This method can return standard HRESULT values, such as E_INVALIDARG or E_OUTOFMEMORY, and VDS-specific return values. It can also return converted system error codes using the HRESULT_FROM_WIN32 macro. Errors can originate from VDS itself or from the underlying VDS provider that is being used. Possible return values include the following.

Return code Description
S_OK
 The method completed successfully.

Remarks

A virtual disk can be merged only if it is detached.

This method moves all data blocks from the child disk to the parent. However, it will not delete the invalidated child disks at the end of the operation.

The virtual disk must have been opened with read/write access.

Requirements

Requirement Value
Minimum supported client Windows 7 [desktop apps only]
Minimum supported server Windows Server 2008 R2 [desktop apps only]
Target Platform Windows
Header vds.h
Library Uuid.lib

See also

IVdsOpenVDisk