Proposal for redesigning the TTY layer

Marcel Moolenaar xcllnt at
Wed Feb 13 10:28:59 PST 2008

On Feb 13, 2008, at 7:05 AM, Ed Schouten wrote:

> The last couple of days I've been working on a document which  
> describes
> the changes I'm going to perform. I have just finished this  
> document, so
> I'm sending it to this list, so you can give your opinion on this
> matter.

You mention the console. It would be best not to tie it up
with the TTY layer, because we typically need the console
way before we can have a TTY layer. A better approach would
be to treat the console as a logging facility that can log
to various destinations. The message buffer is one, a
system console can be another. That system console should
use the TTY layer so that it can accept input. The reason
not to tie them and instead think of printf() as a logging
request is that it makes matters simpler in a multi-console

Also, it may be worthwhile to keep Unicode in mind when you
are reworking the clists. If the TTY layer operates on
wchar_t instead of char, then all it needs is a device driver
that consumes the wchar_t to have native Unicode support.
Non-Unicode drivers can use UTF-8 interfaces.


Marcel Moolenaar
xcllnt at

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