NdisMapFile (NDIS 5.1) function
Note NDIS 5. x has been deprecated and is superseded by NDIS 6. x. For new NDIS driver development, see Network Drivers Starting with Windows Vista. For information about porting NDIS 5. x drivers to NDIS 6. x, see Porting NDIS 5.x Drivers to NDIS 6.0.
NdisMapFile maps an already open file into a caller-accessible buffer if the file is currently unmapped.
Syntax
VOID NdisMapFile(
_Out_ PNDIS_STATUS Status,
_Out_ PVOID *MappedBuffer,
_In_ NDIS_HANDLE FileHandle
);
Parameters
Status [out]
Pointer to a caller-supplied variable in which this function returns the status of the mapping operation, which can be one of the following:NDIS_STATUS_SUCCESS
The caller has exclusive access to the file contents until NdisUnmapFile is called.
NDIS_STATUS_ALREADY_MAPPED
The caller cannot access the file contents at this time.
MappedBuffer [out]
Pointer to a caller-supplied variable in which this function returns the base virtual address of the mapped file contents or NULL.
FileHandle [in]
Specifies the handle returned by a preceding call to NdisOpenFile.
Return value
None
Remarks
NdisMapFile associates (maps) a virtual address range with an opened file so the driver can access the file contents. NdisMapFile allows only one mapping of a particular file to be outstanding at any time. Consequently, a successful caller is given exclusive access to the file data until NdisUnmapFile or NdisCloseFile is called.
A NIC driver can map and unmap such an open file as necessary, using alternating calls to NdisMapFile and NdisUnmapFile. A call to NdisCloseFile releases the FileHandle and deallocates the buffer containing the file contents.
A NIC driver can call NdisMapFile only during initialization.
Requirements
Target platform |
Universal |
Version |
See NdisMapFile. |
Header |
Ndis.h (include Ndis.h) |
Library |
Ndis.lib |
IRQL |
<= DISPATCH_LEVEL |
See also
DriverEntry of NDIS Protocol Drivers