Re: x2d2

[Anthony Liguori <anthony@codemonkey.ws>]

---- Original message ----
>From: Ian Pratt <Ian.Pratt@cl.cam.ac.uk>  
>
>We thought about the pty approach, but resisted it because we
>thought that in most setups there'd need to be a daemon running
>in user-space to export the console (typically over the network),
>and hence it wasn't worth the effort of turning it into a pty in
>the kernel. 

The daemon we wrote does the pty stuff in user space.  It's particularly
useful in unix becase pty's can be connected to all sorts of interesting
things like remote Xterms and ssh sessions.

One particularly useful feature of pty's is delegation.  Since you can
set pty's with standard unix file permissions (maybe even posix acls?)
you can delegate console access in a pretty sophisticated way.

You cannot easily do that with normal sockets.

>The current approach also minimizes the amount of OS-specific Xen
>privileged interface code, which keeps the people interested in
>using OSes other than Linux in domain 0 happy.

I agree here.  pts's are part of Posix though.  Of course more esoteric
OSes that don't have Posix support will need another mechanism but
they'll probably need a lot of work anyway to be used in dom0.

>I could be persuaded, though...

That's always a good sign :-)

Regards,

>Ian


-------------------------------------------------------
This SF.Net email is sponsored by: IntelliVIEW -- Interactive Reporting
Tool for open source databases. Create drag-&-drop reports. Save time
by over 75%! Publish reports on the web. Export to DOC, XLS, RTF, etc.
Download a FREE copy at http://www.intelliview.com/go/osdn_nl