DA_GET_NFS_ATTRIBUTES control code
The DA_GET_NFS_ATTRIBUTES control code queries additional information about an NFS share.
To perform this operation, call the DeviceIoControl function with the following parameters.
BOOL
WINAPI
DeviceIoControl( (HANDLE) hDevice, // handle to device
(DWORD) DA_GET_NFS_ATTRIBUTES, // dwIoControlCode
NULL, // lpInBuffer
0, // nInBufferSize
(LPDWORD) lpOutBuffer, // output buffer
(DWORD) nOutBufferSize, // size of output buffer
(LPDWORD) lpBytesReturned, // number of bytes returned
(LPOVERLAPPED) lpOverlapped ); // OVERLAPPED structure
Parameters
-
hDevice [in]
-
A handle to a file on the NFS share. To obtain this handle, call the CreateFile function.
-
dwIoControlCode [in]
-
The control code for the operation. Use DA_GET_NFS_ATTRIBUTES for this operation.
-
lpInBuffer
-
Not used with this operation; set to NULL.
-
nInBufferSize [in]
-
Not used with this operation; set to zero.
-
lpOutBuffer [out]
-
A pointer to the output buffer, which contains an NFS_FILE_ATTRIBUTES structure. For more information, see the Remarks section.
-
nOutBufferSize [in]
-
The size of the output buffer, in bytes.
-
lpBytesReturned [out]
-
A pointer to a variable that receives the size of the data stored in the output buffer, in bytes.
If the output buffer is too small, the call fails, GetLastError returns ERROR_INSUFFICIENT_BUFFER, and lpBytesReturned is zero.
If lpOverlapped is NULL, lpBytesReturned cannot be NULL. Even when an operation returns no output data and lpOutBuffer is NULL, DeviceIoControl makes use of lpBytesReturned. After such an operation, the value of lpBytesReturned is meaningless.
If lpOverlapped is not NULL, lpBytesReturned can be NULL. If this parameter is not NULL and the operation returns data, lpBytesReturned is meaningless until the overlapped operation has completed. To retrieve the number of bytes returned, call GetOverlappedResult. If the hDevice parameter is associated with an I/O completion port, you can retrieve the number of bytes returned by calling GetQueuedCompletionStatus.
-
lpOverlapped [in]
-
A pointer to an OVERLAPPED structure.
If hDevice was opened without specifying FILE_FLAG_OVERLAPPED, lpOverlapped is ignored.
If hDevice was opened with the FILE_FLAG_OVERLAPPED flag, the operation is performed as an overlapped (asynchronous) operation. In this case, lpOverlapped must point to a valid OVERLAPPED structure that contains a handle to an event object. Otherwise, the function fails in unpredictable ways.
For overlapped operations, DeviceIoControl returns immediately, and the event object is signaled when the operation has been completed. Otherwise, the function does not return until the operation has been completed or an error occurs.
Return value
If the operation completes successfully, DeviceIoControl returns a nonzero value.
If the operation fails or is pending, DeviceIoControl returns zero. To get extended error information, call GetLastError.
Remarks
This control code has no associated header file. You must define the control code and data structures as follows.
#define DEVICE_DA_RDR 0x80000
#define DA_GET_NFS_ATTRIBUTES CTL_CODE(DEVICE_DA_RDR, 0x804, METHOD_BUFFERED, FILE_ANY_ACCESS)
typedef struct _NFS_SPEC_DATA {
ULONG SpecData1;
ULONG SpecData2;
} NFS_SPEC_DATA, *PNFS_SPEC_DATA;
typedef struct _NFS_TIME {
ULONG Seconds;
ULONG nSeconds;
} NFS_TIME, *PNFS_TIME;
#define NFS_TYPE_REG 1
#define NFS_TYPE_DIR 2
#define NFS_TYPE_BLK 3
#define NFS_TYPE_CHR 4
#define NFS_TYPE_LNK 5
#define NFS_TYPE_SOCK 6
#define NFS_TYPE_FIFO 7
typedef struct _NFS_FILE_ATTRIBUTES {
ULONG FileType;
ULONG Mode;
ULONG NLink;
ULONG Uid;
ULONG Gid;
ULONGLONG Size;
ULONGLONG Used;
NFS_SPEC_DATA Rdev;
ULONGLONG Fsid;
ULONGLONG FileId;
NFS_TIME AccessTime;
NFS_TIME ModifyTime;
NFS_TIME ChangeTime;
} NFS_FILE_ATTRIBUTES, *PNFS_FILE_ATTRIBUTES;
typedef struct _DA_FILE_ATTRIBUTES {
NFS_FILE_ATTRIBUTES FileAttributes;
ULONG Version;
} DA_FILE_ATTRIBUTES, *PDA_FILE_ATTRIBUTES;
The structure members can be described as follows.
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SpecData1
-
An opaque value that is used for special file types such as block-special, character-special and FIFO files.
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SpecData2
-
An opaque value that is used for special file types such as block-special, character-special and FIFO files.
-
Seconds
-
A 64-bit value representing the seconds since January 1, 1970 (UTC).
-
nSeconds
-
The number of nanoseconds to be added to the Seconds member.
-
FileType
-
The NFS file type of the share.
NFS File Type Description NFS_TYPE_REG A regular file. NFS_TYPE_DIR A directory. NFS_TYPE_BLK A block-special file. NFS_TYPE_CHR A character-special file. NFS_TYPE_LNK A symbolic link. NFS_TYPE_SOCK A Windows socket. NFS_TYPE_FIFO A FIFO file. -
Mode
-
The file mode.
-
NLink
-
The number of links to the share.
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Uid
-
The UNIX user identifier (UID).
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Gid
-
The UNIX group identifier (GID).
-
Size
-
The file size, in bytes.
-
Used
-
The file size used, in bytes. This is the same as the file size.
-
Rdev
-
The device identifier.
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Fsid
-
The file system identifier.
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FileId
-
The file identifier.
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AccessTime
-
The last access time.
-
ModifyTime
-
The last modification time.
-
ChangeTime
-
The last change time.
-
FileAttributes
-
An NFS_FILE_ATTRIBUTES structure.
Note
For more detailed descriptions of the members of this structure, see the fattr3 structure in the NFS Version 3 Protocol Specification (as defined in RFC 1813).
-
Version
-
Specifies whether the connection on which the handle to the NFS share was created is over NFS Version 2 or NFS Version 3 protocol.
Value Description 2 NFS Version 2 3 NFS Version 3
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client |
None supported |
| Minimum supported server |
Windows Server 2008 |
| End of client support |
None supported |
| End of server support |
Windows Server 2008 R2 |
See also