2.3.33 FSCTL_GET_RETRIEVAL_POINTERS_AND_REFCOUNT Request

The FSCTL_GET_RETRIEVAL_POINTERS_AND_REFCOUNT request message requests that the server return a list of extents and their reference counts for the file or directory associated with the handle on which this FSCTL was invoked. The extents describe the mapping between virtual cluster numbers (VCNs) and logical cluster numbers (LCNs). The reference count describes how many times these logical cluster numbers (LCNs) are being used within the volume. This request is most commonly used by deduplication utilities. This message contains a STARTING_VCN_INPUT_BUFFER data element.<30>

The STARTING_VCN_INPUT_BUFFER data element is as follows.


0


1


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8


9

1
0


1


2


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8


9

2
0


1


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9

3
0


1

StartingVcn

...

StartingVcn (8 bytes): A 64-bit signed integer that contains the virtual cluster number (VCN) at which to begin retrieving extents in the file. This value MUST be greater than or equal to 0.