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Returns information about the number of partitions, disk signature, and features of each partition on a disk. (Floppy drivers need not handle this request.)

Input Parameters

Parameters.DeviceIoControl.OutputBufferLength in the I/O stack location of the IRP indicates the size, in bytes, of the buffer, which must be >= sizeof(DRIVE_LAYOUT_INFORMATION_EX). Note that this structure contains a variable-sized array of PARTITION_INFORMATION_EX elements.

Output Parameters

The driver returns the DRIVE_LAYOUT_INFORMATION_EX data in the buffer at Irp->AssociatedIrp.SystemBuffer.

To determine the size of output buffer that is required, caller should send this IOCTL request in a loop. Every time the storage stack rejects the IOCTL with an error message indicating that the buffer was too small, caller should double the buffer size.

I/O Status Block

The Information field is set to the size, in bytes, of the returned data. The Status field can be set to STATUS_SUCCESS, or possibly to STATUS_INFO_LENGTH_MISMATCH, STATUS_INSUFFICIENT_RESOURCES, or STATUS_BUFFER_TOO_SMALL.



Ntdddisk.h (include Ntdddisk.h)

See also




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