REPARSE_DATA_BUFFER structure (ntifs.h)
The REPARSE_DATA_BUFFER structure contains reparse point data for a Microsoft reparse point. You can use REPARSE_DATA_BUFFER_EX instead. (Third-party reparse point owners must use the REPARSE_GUID_DATA_BUFFER structure instead.)
Syntax
typedef struct _REPARSE_DATA_BUFFER {
ULONG ReparseTag;
USHORT ReparseDataLength;
USHORT Reserved;
union {
struct {
USHORT SubstituteNameOffset;
USHORT SubstituteNameLength;
USHORT PrintNameOffset;
USHORT PrintNameLength;
ULONG Flags;
WCHAR PathBuffer[1];
} SymbolicLinkReparseBuffer;
struct {
USHORT SubstituteNameOffset;
USHORT SubstituteNameLength;
USHORT PrintNameOffset;
USHORT PrintNameLength;
WCHAR PathBuffer[1];
} MountPointReparseBuffer;
struct {
UCHAR DataBuffer[1];
} GenericReparseBuffer;
} DUMMYUNIONNAME;
} REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
Members
ReparseTag
Reparse point tag. Must be a Microsoft reparse point tag. (See the following Remarks section.)
ReparseDataLength
Size, in bytes, of the reparse data in the buffer that DataBuffer points to.
Reserved
Length, in bytes, of the unparsed portion of the file name pointed to by the FileName member of the associated file object. For more information about the FileName member, see FILE_OBJECT<. This member is only valid for create operations when the I/O fails with STATUS_REPARSE. For all other purposes, such as setting or querying a reparse point for the reparse data, this member is treated as reserved.
DUMMYUNIONNAME
DUMMYUNIONNAME.SymbolicLinkReparseBuffer
DUMMYUNIONNAME.SymbolicLinkReparseBuffer.SubstituteNameOffset
Offset, in bytes, of the substitute name string in the PathBuffer array. Note that this offset must be divided by sizeof(WCHAR) to get the array index.
DUMMYUNIONNAME.SymbolicLinkReparseBuffer.SubstituteNameLength
Length, in bytes, of the substitute name string. If this string is NULL-terminated, SubstituteNameLength does not include space for the UNICODE_NULL terminator.
DUMMYUNIONNAME.SymbolicLinkReparseBuffer.PrintNameOffset
Offset, in bytes, of the print name string in the PathBuffer array. Note that this offset must be divided by sizeof(WCHAR) to get the array index.
DUMMYUNIONNAME.SymbolicLinkReparseBuffer.PrintNameLength
Length, in bytes, of the print name string. If this string is NULL-terminated, PrintNameLength does not include space for the UNICODE_NULL terminator.
DUMMYUNIONNAME.SymbolicLinkReparseBuffer.Flags
Indicates whether the symbolic link is absolute or relative. If Flags contains SYMLINK_FLAG_RELATIVE, the symbolic link contained in the PathBuffer array (at offset SubstituteNameOffset) is processed as a relative symbolic link; otherwise, it is processed as an absolute symbolic link.
DUMMYUNIONNAME.SymbolicLinkReparseBuffer.PathBuffer[1]
First character of the path string. This character is followed in memory by the remainder of the string. The path string contains the substitute name string and print name string. The substitute name and print name strings can appear in any order in the PathBuffer. To locate the substitute name and print name strings in the PathBuffer, use the SubstituteNameOffset, SubstituteNameLength, PrintNameOffset, and PrintNameLength members.
DUMMYUNIONNAME.MountPointReparseBuffer
DUMMYUNIONNAME.MountPointReparseBuffer.SubstituteNameOffset
Offset, in bytes, of the substitute name string in the PathBuffer array. Note that this offset must be divided by sizeof(WCHAR) to get the array index.
DUMMYUNIONNAME.MountPointReparseBuffer.SubstituteNameLength
Length, in bytes, of the substitute name string. If this string is NULL-terminated, SubstituteNameLength does not include space for the UNICODE_NULL terminator.
DUMMYUNIONNAME.MountPointReparseBuffer.PrintNameOffset
Offset, in bytes, of the print name string in the PathBuffer array. Note that this offset must be divided by sizeof(WCHAR) to get the array index.
DUMMYUNIONNAME.MountPointReparseBuffer.PrintNameLength
Length, in bytes, of the print name string. If this string is NULL-terminated, PrintNameLength does not include space for the UNICODE_NULL terminator.
DUMMYUNIONNAME.MountPointReparseBuffer.PathBuffer[1]
First character of the path string. This character is followed in memory by the remainder of the string. The path string contains the substitute name string and print name string. The substitute name and print name strings can appear in any order in the PathBuffer. To locate the substitute name and print name strings in the PathBuffer, use the SubstituteNameOffset, SubstituteNameLength, PrintNameOffset, and PrintNameLength members.
DUMMYUNIONNAME.GenericReparseBuffer
DUMMYUNIONNAME.GenericReparseBuffer.DataBuffer[1]
Pointer to a buffer that contains Microsoft-defined data for the reparse point.
Remarks
The REPARSE_DATA_BUFFER structure is used by Microsoft file systems, filters, and minifilter drivers, as well as the I/O manager, to store data for a reparse point.
This structure can only be used for Microsoft reparse points. Third-party reparse point owners must use the REPARSE_GUID_DATA_BUFFER structure instead.
Microsoft reparse points can use the REPARSE_DATA_BUFFER structure or the REPARSE_GUID_DATA_BUFFER structure.
From the union, you can use the GenericReparseBuffer structure to interpret the payload for any IO_REPARSE_TAG_XXX tag, or optionally use one of the other structures within the union as follows:
Use the SymbolicLinkReparseBuffer structure when FileTag is IO_REPARSE_TAG_SYMLINK.
Use the MountPointReparseBuffer structure when FileTag is IO_REPARSE_TAG_MOUNT_POINT.
For more information about reparse point tags, see the Microsoft Windows SDK documentation.
Requirements
| Requirement | Value |
|---|---|
| Header | ntifs.h (include Ntifs.h, Fltkernel.h) |
See also
FILE_REPARSE_POINT_INFORMATION