FltFsControlFile function (fltkernel.h)
The FltFsControlFile routine sends a control code directly to a specified file system or file system filter driver, causing the corresponding driver to perform the specified action.
Syntax
NTSTATUS FLTAPI FltFsControlFile(
[in] PFLT_INSTANCE Instance,
[in] PFILE_OBJECT FileObject,
[in] ULONG FsControlCode,
[in, optional] PVOID InputBuffer,
[in] ULONG InputBufferLength,
[out, optional] PVOID OutputBuffer,
[in] ULONG OutputBufferLength,
[out, optional] PULONG LengthReturned
);
Parameters
[in] Instance
Opaque instance pointer for the caller. This parameter is required and cannot be NULL.
[in] FileObject
File object pointer for the file or directory that is the target of this request. This parameter is required and cannot be NULL.
[in] FsControlCode
FSCTL_XXX code that indicates which file system operation is to be carried out. The value of this parameter determines the formats and required lengths of the InputBuffer and OutputBuffer, and it determines which of the following parameter pairs (InputBuffer and InputBufferLength, OutputBuffer and OutputBufferLength) is required.
[in, optional] InputBuffer
Pointer to a caller-allocated input buffer that contains device-specific information to be given to the target driver. If the FsControlCode parameter specifies an operation that does not require input data, this parameter is optional and can be NULL.
[in] InputBufferLength
Size, in bytes, of the buffer at InputBuffer. This value is ignored if InputBuffer is NULL.
[out, optional] OutputBuffer
Pointer to a caller-allocated output buffer in which information is returned from the target driver. If the FsControlCode parameter specifies an operation that does not require output data, this parameter is optional and can be NULL.
[in] OutputBufferLength
Size, in bytes, of the buffer at OutputBuffer. This value is ignored if OutputBuffer is NULL.
[out, optional] LengthReturned
Pointer to a caller-allocated variable that receives the size, in bytes, of the information returned in the buffer at OutputBuffer. This parameter is optional and can be NULL.
Return value
FltFsControlFile returns STATUS_SUCCESS or an appropriate NTSTATUS value.
Remarks
Minifilter drivers should call this routine instead of ZwFsControlFile.
The following FSCTL codes are currently documented for kernel-mode drivers:
FSCTL_OPBATCH_ACK_CLOSE_PENDING
FSCTL_OPLOCK_BREAK_ACKNOWLEDGE
For more information about the system-defined FSCTL_XXX codes, see the Remarks section of the reference entry for DeviceIoControl in the Microsoft Windows SDK documentation.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Universal |
| Header | fltkernel.h (include Fltkernel.h) |
| Library | FltMgr.lib |
| DLL | Fltmgr.sys |
| IRQL | PASSIVE_LEVEL |