FS_EnumerateHandle

FS_EnumerateHandle(
 PIOREQ pir
 )

This function handles the Win32 function: GetFileInformationByHandle() and the DOS int 21h function: 440dh, subfunction 086dh. In addition, it also handles certain operations that are needed for volume locking support in the IFS manager.

ir_rh

Supplies handle to disk volume or network resource which contains the file.

ir_sfn

Supplies system file number.

ir_flags

Supplies operation type.

Operation Type Values:
Value	Meaning
ENUMH_GETFILEINFO	Get information about the file.
ENUMH_GETFILENAME	Get the pathname of the file.
ENUMH_GETFINDINFO	Get information about the find handle so that a find can be resumed after a volume lock is released.
ENUMH_RESUMEFIND	Resume a find based on the information returned on the ENUMH_GETFINDINFO operation called previously.
ENUMH_RESYNCFILEDIR	Resynchronize the directory cluster and position for a file that could have been moved. However, the file's data blocks will not have moved.

ir_fh

Supplies the FSD file handle on the ENUMH_GETFILEINFO, ENUMH_GETFILENAME and the ENUMH_RESYNCFILEDIR operations. Supplies the FSD find handle on the ENUMH_GETFINDINFO and ENUMH_RESUMEFIND operations.

ir_ppath

Supplies the pathname on ENUMH_RESUMEFIND and ENUMH_RESYNCFILEDIR operations. Supplies a pointer to a buffer the pathname is to be returned in on the ENUMH_GETFINDINFO and ENUMH_GETFILENAME operations. This parameter is not valid on the ENUMH_GETFILEINFO operation.

ir_data

Supplies a pointer to the structure filled in on the ENUMH_GETFILEINFO operation. The contents of this structure are described below. This parameter is not valid on other operations.

ir_options

Supplies special options. This field is valid only on the ENUMH_RESYNCFILEDIR operation.

ENUMH_RESYNCFILEDIR Options:
Value	Meaning
RESYNC_INVALIDATEMETACACHE	Indicates that any meta-caches associated with this open file should be flushed. This could include file extent caches, name caches etc.

ir_user

Supplies user id for this request.

ir_pid

Supplies process id for this request.

ir_error

Contains status of the operation ( 0 if no error, errorcode otherwise ) for all operations.

Operation Type ENUMHGETFILEINFO:
Value	Meaning
ir_data	Returns information about the file filled into the BY_HANDLE_FILE_INFORMATION structure described below.

BY_HANDLE_FILE_INFORMATION Structure:
Value	Meaning
bhfi_dwFileAttributes	Returns the attributes of the file.
bhfi_ftCreationTime	Returns the creation time of the file in the Win32 FileTime structure format described below.

Win32 FileTime Structure:
Value	Meaning
dwLowDateTime	Returns the low double word of the time in Win32 format.
dwHighDateTime	Returns the high double word of the time in Win32 format.

bhfi_ftLastAccessTime	Returns the last access time of the file in the Win32 FileTime structure format described above.
bhfi_ftLastWriteTime	Returns the last access time of the file in the Win32 FileTime structure format described above.
bhfi_dwVolumeSerialNumber	Returns the serial number of the volume the file is on.
bhfi_nFileSizeHigh	Returns the high 32-bits of the file size.
bhfi_nFileSizeLow	Returns the low 32-bits of the file size.
bhfi_nNumberOfLinks	Returns the number of links to the file.
bhfi_nFileIndexHigh	Returns the high 32-bits of a unique index to the file. This index needs to be valid only while the file is open and is typically used to determine if multiple handles point to the same open file.
bhfi_nFileIndexLow	Returns the low 32-bits of a unique index to the file.

Operation Type ENUMHGETFILENAME:
Value	Meaning
ir_ppath	Returns the pathname to the open file in a unicode canonicalized path format. This path can be passed back to the FSD to open the file.

Operation Type ENUMHGETFINDINFO:
Value	Meaning
ir_ppath	Returns the pathname to the last file found on the find handle in a unicode canonicalized path format. This path can be passed back to the FSD to resume the find at this pathname. This is typically done during volume locking.

Details about volume locking support and about how these volume locking operations are used to ensure a consistent system while a volume lock is in progress are given in the volume locking specification. Any local FSD that allows direct disk operations must also support the volume locking support functions. Note that the ENUMH_RESYNCFILEDIR operation can only be called on files that are left open by the IFS manager across a level 3 volume lock. Typically, memory-mapped files and Win32 executables and DLLs fall into this category of files. However, disk utilities are allowed to move these files even though they are open, with certain restrictions.