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DISK_EX_INT13_INFO structure (ntdddisk.h)

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The DISK_EX_INT13_INFO structure is used by the BIOS to report disk detection data for a partition with an extended INT13 format.

Syntax

typedef struct _DISK_EX_INT13_INFO {
  USHORT  ExBufferSize;
  USHORT  ExFlags;
  ULONG   ExCylinders;
  ULONG   ExHeads;
  ULONG   ExSectorsPerTrack;
  ULONG64 ExSectorsPerDrive;
  USHORT  ExSectorSize;
  USHORT  ExReserved;
} DISK_EX_INT13_INFO, *PDISK_EX_INT13_INFO;

Members

ExBufferSize

Indicates the size of the buffer that the caller provides to the BIOS in which to return the requested drive data. ExBufferSize must be 26 or greater. If ExBufferSize is less than 26, the BIOS returns an error . If ExBufferSize is between 30 and 66, the BIOS sets it to exactly 30 on exit. If ExBufferSize is 66 or greater, the BIOS sets it to exactly 66 on exit.

ExFlags

Provides information about the drive. The following table describes the significance of each bit, where bit 0 is the least significant bit and bit 15 the most significant bit. A value of one in the indicated bit means that the feature described in the "Meaning" column is available. A value of zero in the indicated bit means that the feature is not available with this drive.

Bit number Meaning
0 DMA boundary errors are handled transparently.
1 The geometry supplied in bytes 8-12 is valid.
2 Device is removable.
3 Device supports write with verify.
4 Device has change line support (bit 2 must be set).
5 Device is lockable (bit 2 must be set).
6 Device geometry is set to maximum, no media is present (bit 2 must be set). This bit is turned off when media is present in a removable media device.
7-15 Reserved, must be 0.

ExCylinders

Indicates the number of physical cylinders. This is one greater than the maximum cylinder number.

ExHeads

Indicates the number of physical heads. This is one greater than the maximum head number.

ExSectorsPerTrack

Indicates the number of physical sectors per track. This number is the same as the maximum sector number.

ExSectorsPerDrive

Indicates the total count of sectors on the disk. This is one greater than the maximum logical block address.

ExSectorSize

Indicates the sector size in bytes.

ExReserved

Reserved.

Requirements

Requirement Value
Header ntdddisk.h (include Ntdddisk.h)

See also

DISK_DETECTION_INFO

DISK_INT13_INFO