Just a thought on OS specific features

Robert Schmidt rsc "at" vingmed.no
Wed, 18 Mar 1998 15:29:43 +0000

Some time ago, almost everybody brought up the problem with passing
Alt+Ctrl+Del to Windows servers.  There are bound to be other host
specific features for other platforms which have to be supported by all

Such features are (usually?) independent of the client side OS, and a
protocol for detecting these features should be added to the initial

For example, when connection is established, the client asks the server: 
"Uhm... by the way, do you have any specific functions (I don't really
care what they do, but my user does), that you wish me to present to my

The server replies:
"Ah!  Glad you asked!  Actually, there are a couple of actions which
can't be conveyed through the mouse and keyboard interface.  I'll give
you descriptions that you can show the user, as well as event IDs you
can send me when your user wants to initiate them.  
There are 3 such actions, as follows:
'Send Alt+Ctrl+Del': 10001
'Send Alt-Down+Tab': 10002
'Send Ctrl+Esc': 10003"

The client is then able to present these actions as buttons or menu
items (this could be configurable through hints from the server, and/or
through a user setting in the client) without knowing or caring what
they actually do on the server side.  Mac-servers can do something
similar with their funny keys, and a Linux-specific server could add the
console switching key-combos (if it will ever support consoles other
than the one running X).

Another idea around the key-combo issue is to have the client ask the
server for a verbose keyboard map.  A button in the client pops up such
a map (which needs only be a list of all the keys).  The user then
selects one or more keys, and sends them to the server with another

I apologize if this was really obvious, is already done in a similar or
better way, or otherwise too silly... :)  I also admit I haven't paid
too close attention to the VNC protocol/sources and how it actually

Robert Schmidt <rsc "at" vingmed.no>
Software Developer / Vingmed Sound tel +47 67124237 fax +47 67124355
Private tel +47 22606076 WWW http://www.nvg.unit.no/~rsc

    jeg lukker et oye og ser halvt
    jeg  lukker begge  og ser  alt            -- seigmen