The FSCTL_GET_RETRIEVAL_POINTERS reply message returns the results of the FSCTL_GET_RETRIEVAL_POINTERS request as a variably sized data element, RETRIEVAL_POINTERS_BUFFER, that specifies the allocation and location on disk of a specific file.For the NTFS file system, the FSCTL_GET_RETRIEVAL_POINTERS reply returns the extent locations (that is, locations of allocated regions of disk space) of nonresident data. A file system MAY allow resident data, which is data that can be written to disk within the file's directory record. Because resident data requires no additional disk space allocation, no extent locations are associated with resident data.On an NTFS volume, very short data streams (typically several hundred bytes) can be written to disk without having any clusters allocated. These short streams are sometimes called resident because the data resides in the file's master file table (MFT) record. A resident data stream has no retrieval pointers to return.The RETRIEVAL_POINTERS_BUFFER data element is as follows.
