Re: New line discipline flag to prevent userland open/close of the device

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

>> Disabling user opens, by any means, would make such things
>> significantly more difficult.
> Hmm, indeed.  In the end we don't realy care as long as that open
> does not change the serial communication parameters.

I'm not sure even that is good.  I have at least one Sun mouse which
runs at 9600 instead of 1200 - I modded it as an experiment, and it
really does improve interactive responsiveness.  (I also hacked on the
mouse code to cycle baudrates, as a sort of poor-man's autobaud, as
well as adding keyboard controls to kmmux to forcibly cycle baudrates,
so it's not actually necessary for me.  But then, since NetBSD is open
source - or, at least, these bits are - and I'm competent to hack on
the code, none of this is necessary for me.)

> My initial try was to make sure the ioctls changing those get
> rejected, but that was not enough,

This could be done by, rather than rejecting the ioctls, providing a
set-modes implementation that refuses to modify certain aspects.

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