2.4.3 FileAlignmentInformation

This information class is used to query the buffer alignment required by the underlying device.

A FILE_ALIGNMENT_INFORMATION data element, defined as follows, is returned by the server.

0	1	2	3	4	5	6	7	8	9	1 0	1	2	3	4	5	6	7	8	9	2 0	1	2	3	4	5	6	7	8	9	3 0	1
AlignmentRequirement

AlignmentRequirement (4 bytes):  A 32-bit unsigned integer that MUST contain one of the following values.

Value	Meaning
FILE_BYTE_ALIGNMENT 0x00000000	Specifies that there are no alignment requirements for the device.
FILE_WORD_ALIGNMENT 0x00000001	Specifies that data MUST be aligned on a 2-byte boundary.
FILE_LONG_ALIGNMENT 0x00000003	Specifies that data MUST be aligned on a 4-byte boundary.
FILE_QUAD_ALIGNMENT 0x00000007	Specifies that data MUST be aligned on an 8-byte boundary.
FILE_OCTA_ALIGNMENT 0X0000000F	Specifies that data MUST be aligned on a 16-byte boundary.
FILE_32_BYTE_ALIGNMENT 0X0000001F	Specifies that data MUST be aligned on a 32-byte boundary.
FILE_64_BYTE_ALIGNMENT 0X0000003F	Specifies that data MUST be aligned on a 64-byte boundary.
FILE_128_BYTE_ALIGNMENT 0X0000007F	Specifies that data MUST be aligned on a 128-byte boundary.
FILE_256_BYTE_ALIGNMENT 0X000000FF	Specifies that data MUST be aligned on a 256-byte boundary.
FILE_512_BYTE_ALIGNMENT 0X000001FF	Specifies that data MUST be aligned on a 512-byte boundary.

This operation returns a status code as specified in section 2.2. Upon success, the status code returned by the function that processes this file information class is STATUS_SUCCESS. The most common error codes are listed in the following table.

Error code	Meaning
STATUS_INFO_LENGTH_MISMATCH 0xC0000004	The specified information record length does not match the length that is required for the specified information class.