The message is accepted by the filtering.
Any further Check Message Filter Hooks in the chain are ignored, any filtering
specified by the ulFirst and ulLast parameters of the WinGetMsg,
WinPeekMsg or WinWaitMsg
functions are ignored, and processing of the message continues.
A hook that always returns TRUE effectively switches off message filtering.
FALSE
The message is passed
on to the next Check Message Filter Hook in the chain. If the end of the
chain has been reached, the filtering specified by the ulFirst and
ulLast parameters of the WinGetMsg,
WinPeekMsg or WinWaitMsg
functions is applied.