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IOCTL_DISK_GET_PARTITION_INFO IOCTL (winioctl.h)

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Retrieves information about the type, size, and nature of a disk partition.

Note

IOCTL_DISK_GET_PARTITION_INFO is superseded by IOCTL_DISK_GET_PARTITION_INFO_EX, which retrieves partition information for AT and Extensible Firmware Interface (EFI) partitions.

To perform this operation, call the DeviceIoControl function with the following parameters.

BOOL DeviceIoControl(
  (HANDLE) hDevice,                 // handle to a partition
  IOCTL_DISK_GET_PARTITION_INFO,    // 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
);

Remarks

The IOCTL_DISK_GET_PARTITION_INFO control code is only supported on MBR-formatted disks.

The disk support can be summarized as follows.

Disk type IOCTL_DISK_GET_PARTITION_INFO IOCTL_DISK_GET_PARTITION_INFO_EX
Basic master boot record (MBR) Yes Yes
Basic GUID partition table (GPT) No Yes
Dynamic MBR boot/system Yes Yes
Dynamic MBR data Yes No
Dynamic GPT boot/system No Yes
Dynamic GPT data No No

Currently, GPT is supported only on 64-bit systems.

If the partition is on a disk formatted as type master boot record (MBR), partition size totals are limited. For more information, see the Remarks section of IOCTL_DISK_SET_DRIVE_LAYOUT.

Requirements

Requirement Value
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