NdisMapFile function (ndis.h)
The NdisMapFile function 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
[out] Status
A 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 the NdisUnmapFile function is called.
NDIS_STATUS_ALREADY_MAPPED
The caller cannot access the file contents at this time.
[out] MappedBuffer
A pointer to a caller-supplied variable in which this function returns the base virtual address of the mapped file contents or NULL.
[in] FileHandle
The handle that was returned by a preceding call to the NdisOpenFile function.
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 the NdisCloseFile function is called.
A miniport 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 miniport driver can call NdisMapFile only during initialization.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Supported for NDIS 6.0 and NDIS 5.1 drivers (see NdisMapFile (NDIS 5.1)) in Windows Vista. Supported for NDIS 5.1 drivers (see NdisMapFile (NDIS 5.1)) in Windows XP. |
| Target Platform | Universal |
| Header | ndis.h (include Video.h) |
| Library | Ndis.lib |
| IRQL | <= DISPATCH_LEVEL |
| DDI compliance rules | Irql_Miscellaneous_Function(ndis) |