he note 255 is regarded
as velocity change, and key pressure event is passed to the port. In <TT>PASS_EVENTS</TT>
mode, all note on/off events are passed to the port without modified. <TT>PROCESS_KEYPRESS</TT>
mode checks the note above 128 and regards it as key pressure event (mainly
for Emu8000 driver).
<H4>
7.2.1. Open Callback</H4>
The <TT>open</TT> is called at each time this device is opened by an application
using OSS sequencer. This must not be NULL. Typically, the open callback
does the following p