Export (0) Print
Expand All

IOCTL_DISK_GET_DRIVE_LAYOUT control code

Retrieves information for each entry in the partition tables for a disk.

Note  IOCTL_DISK_GET_DRIVE_LAYOUT has been superseded by IOCTL_DISK_GET_DRIVE_LAYOUT_EX, which retrieves layout information for AT and EFI (Extensible Firmware Interface) partitions.

To perform this operation, call the DeviceIoControl function with the following parameters. You must have read access to the drive in order to use this control code.



BOOL DeviceIoControl(
  (HANDLE) hDevice,            // handle to device
  IOCTL_DISK_GET_DRIVE_LAYOUT, // dwIoControlCode
  NULL,                        // lpInBuffer
  0,                           // nInBufferSize
  (LPVOID) lpOutBuffer,        // output buffer
  (DWORD) nOutBufferSize,      // size of output buffer
  (LPDWORD) lpBytesReturned,   // number of bytes returned
  (LPOVERLAPPED) lpOverlapped  // OVERLAPPED structure
);

Parameters

hDevice

A handle to the disk device from which the drive layout is to be retrieved. To obtain a device handle, call the CreateFile function.

dwIoControlCode

The control code for the operation. Use IOCTL_DISK_GET_DRIVE_LAYOUT for this operation.

lpInBuffer

Not used with this operation; set to NULL.

nInBufferSize

Not used with this operation; set to zero.

lpOutBuffer

A pointer to a buffer that receives a DRIVE_LAYOUT_INFORMATION structure.

nOutBufferSize

The size of the output buffer, in bytes.

lpBytesReturned

A pointer to a variable that receives the size of the data stored in the output buffer, in bytes.

If the output buffer is too small, the call fails, GetLastError returns ERROR_INSUFFICIENT_BUFFER, and lpBytesReturned is zero.

If lpOverlapped is NULL, lpBytesReturned cannot be NULL. Even when an operation returns no output data and lpOutBuffer is NULL, DeviceIoControl makes use of lpBytesReturned. After such an operation, the value of lpBytesReturned is meaningless.

If lpOverlapped is not NULL, lpBytesReturned can be NULL. If this parameter is not NULL and the operation returns data, lpBytesReturned is meaningless until the overlapped operation has completed. To retrieve the number of bytes returned, call GetOverlappedResult. If hDevice is associated with an I/O completion port, you can retrieve the number of bytes returned by calling GetQueuedCompletionStatus.

lpOverlapped

A pointer to an OVERLAPPED structure.

If hDevice was opened without specifying FILE_FLAG_OVERLAPPED, lpOverlapped is ignored.

If hDevice was opened with the FILE_FLAG_OVERLAPPED flag, the operation is performed as an overlapped (asynchronous) operation. In this case, lpOverlapped must point to a valid OVERLAPPED structure that contains a handle to an event object. Otherwise, the function fails in unpredictable ways.

For overlapped operations, DeviceIoControl returns immediately, and the event object is signaled when the operation has been completed. Otherwise, the function does not return until the operation has been completed or an error occurs.

Return value

If the operation completes successfully, DeviceIoControl returns a nonzero value.

If the operation fails or is pending, DeviceIoControl returns zero. To get extended error information, call GetLastError.

Remarks

This operation retrieves information for each primary partition as well as each logical drive. To determine whether the entry is an extended or unused partition, check the disk partition type.

Requirements

Minimum supported client

Windows XP [desktop apps only]

Minimum supported server

Windows Server 2003 [desktop apps only]

Header

WinIoCtl.h (include Windows.h)

See also

DeviceIoControl
Disk Management Control Codes
DRIVE_LAYOUT_INFORMATION
IOCTL_DISK_GET_DRIVE_LAYOUT_EX
IOCTL_DISK_SET_DRIVE_LAYOUT

 

 

Community Additions

ADD
Show:
© 2014 Microsoft