FSCTL_USN_TRACK_MODIFIED_RANGES IOCTL

Description

Enables range tracking for the update sequence number (USN) change journal stream on a target volume, or modifies already enabled range tracking parameters.

BOOL DeviceIoControl(
  (HANDLE) hDevice,                 // handle to volume
  FSCTL_USN_TRACK_MODIFIED_RANGES,  // dwIoControlCode
  (LPDWORD) lpInBuffer,             // input buffer
  (DWORD) nInBufferSize,            // size of input buffer
  (LPDWORD) lpOutBuffer,            // lpOutbuffer
  (DWORD) nOutBufferSize,           // size of output buffer
  (LPDWORD) lpBytesReturned,        // number of bytes returned
  (LPOVERLAPPED) lpOverlapped       // OVERLAPPED structure
);

Parameters

Input buffer

Input buffer length

Output buffer

Output buffer length

Input/output buffer

Input/output buffer length

Status block

Remarks

For more details on implications of overlapped I/O on this operation, see the DeviceIoControl remarks.

FSCTL_USN_TRACK_MODIFIED_RANGES can be used to enable range tracking for the first time on a volume. After enabling range tracking, the state and parameters will be persisted for that volume (on reboot, range tracking will be initialized from the persisted parameters).

FSCTL_USN_TRACK_MODIFIED_RANGES can also be used to modify an existing change journal stream range track parameter. If range tracking already exists, FSCTL_USN_TRACK_MODIFIED_RANGES sets it to the parameters provided in the USN_TRACK_MODIFIED_RANGES structure. The chunk size or file size threshold can only be lowered from previous values. Once enabled, the range tracking feature cannot be disabled unless the journal is deleted.

To retrieve a handle to a volume, call CreateFile with the lpFileName parameter set to a string in the following form: \\.\X:

In the preceding string, X is the letter identifying the drive on which the volume appears. The volume must be NTFS 3.0 or later. To obtain the NTFS version of a volume, open a command prompt with Administrator access rights and execute the following command (where X is the drive letter of the volume): fsutil fsinfo ntfsinfo X:

Irp->IoStatus.Status is set to STATUS_SUCCESS if the request is successful. Otherwise, Status is set to the appropriate error condition as a NTSTATUS code. For more information, see NTSTATUS Values.

See also

• DeviceIoControl