FltGetNewSystemBufferAddress function (fltkernel.h)

The FltGetNewSystemBufferAddress function retrieves the AssociatedIrp.SystemBuffer buffer, which the file system has allocated. A minifilter driver's post-callback routine calls this function.

Syntax

PVOID FLTAPI FltGetNewSystemBufferAddress(
  [in] PFLT_CALLBACK_DATA CallbackData
);

Parameters

[in] CallbackData

A pointer to a FLT_CALLBACK_DATA structure that represents an I/O operation.

Return value

If the AssociatedIrp.SystemBuffer buffer was allocated by the file system, FltGetNewSystemBufferAddress returns a pointer to this buffer; otherwise it returns NULL.

Remarks

A minifilter driver's post-callback routine calls FltGetNewSystemBufferAddress function to retrieve a pointer to the AssociatedIrp.SystemBuffer buffer that the file system has allocated. A minifilter driver should call this function only when the FLTFL_CALLBACK_DATA_NEW_SYSTEM_BUFFER flag is set in CallbackData.Flags.

When the file system allocates its own AssociatedIrp.SystemBuffer buffer, Filter Manager will set the FLTFL_CALLBACK_DATA_NEW_SYSTEM_BUFFER flag. This signals the minifilter that the buffer they received in the pre-operation is not the one that has the data read from the file system.

If the FLTFL_CALLBACK_DATA_NEW_SYSTEM_BUFFER flag is not set, then this routine returns NULL.

Requirements

See also

FLT_CALLBACK_DATA