* The 0x1f mask could be useful for some applications. Maybe we could
have this as an extra kernel parameter?
* I did not implement reference counting for 0x2000 pids, because I
thought they would not be added more than once. However thinking about
it now, it seems that this can actually happen to every pid, e.g. if you
run dvbstream and scan at once. Therefore we probably need ref-counting
for all pids? This is a nightmare for implementation and should probably
done using some hash map technique.
We have plenty of space in the hi bits of the two pid lists (0-57343
value range)!
Why don't we do ref-counting in theese unused hi bits.
Should be quick, and no space and code consuming.
...