FILE_FS_SIZE_INFORMATION - NtDoc
Native API online documentation, based on the System Informer
(formerly Process Hacker) phnt
headers
#ifndef _NTIOAPI_H
typedef struct _FILE_FS_SIZE_INFORMATION
{
LARGE_INTEGER TotalAllocationUnits;
LARGE_INTEGER AvailableAllocationUnits;
ULONG SectorsPerAllocationUnit;
ULONG BytesPerSector;
} FILE_FS_SIZE_INFORMATION, *PFILE_FS_SIZE_INFORMATION;
View code on GitHub// ntddk.h
typedef struct _FILE_FS_SIZE_INFORMATION {
LARGE_INTEGER TotalAllocationUnits;
LARGE_INTEGER AvailableAllocationUnits;
ULONG SectorsPerAllocationUnit;
ULONG BytesPerSector;
} FILE_FS_SIZE_INFORMATION, *PFILE_FS_SIZE_INFORMATION;
View the official Windows Driver Kit DDI referenceNo description available.
The FILE_FS_SIZE_INFORMATION structure is used to query sector size information for a file system volume.
TotalAllocationUnitsTotal number of allocation units on the volume that are available to the user associated with the calling thread.
Microsoft Windows 2000 and later: If per-user quotas are in use, this value may be less than the total number of allocation units on the disk.
AvailableAllocationUnitsTotal number of free allocation units on the volume that are available to the user associated with the calling thread.
Windows 2000 and later: If per-user quotas are in use, this value may be less than the total number of free allocation units on the disk.
SectorsPerAllocationUnitNumber of sectors in each allocation unit.
BytesPerSectorNumber of bytes in each sector.
This information can be queried in either of the following ways:
No specific access rights are required to query this information. Thus this information is available as long as the volume is accessed through an open handle to the volume itself, or to a file or directory on the volume.
The size of the buffer passed in the FileInformation parameter to FltQueryVolumeInformation or ZwQueryVolumeInformationFile must be at least sizeof (FILE_FS_SIZE_INFORMATION).
This structure must be aligned on a LONGLONG (8-byte) boundary.
IRP_MJ_QUERY_VOLUME_INFORMATION
This structure is documented in Windows Driver Kit.
Structure provides detailed information about volume physical size. Is returned in call to NtQueryVolumeInformationFile with FileFsSizeInformation information class.