Re: K42 OS

[David Leimbach <leimy2k@xxxxxxx>]

On Nov 21, 2003, at 6:13 PM, Bill Huey (hui) wrote:

> On Thu, Nov 20, 2003 at 07:50:57PM -0500, Michal Ostrowski wrote:
> > On Thu, 2003-11-20 at 19:31, Matthew Dillon wrote:
> > >     I am not trying to create a procedural abstraction, but I do 
> > > intend to use
> > >     messaging to initiate syscalls so in a sense that is a procedural
> > >     abstraction of a kind since it causes things like read() to be 
> > > moved into
> > >     libc and actually build, dispatch, and wait for the syscall 
> > > message
> > >     rather then make a directly 'read' system call.
> ...
> > Underneath all of this, I think there are interesting issues arising
> > from interactions between thread management and IPC.
>
> Like what ? priority messaging issues ? just curious.
>
> > With regard to the second issue you've touched upon, we implement UNIX
> > API's as you've described.  Our approach to this has been to move as
> > much functionality into the application as possible.  Thus things such
> > as file-cursor management can be handled within the application under
> > certain circumstances, and poll()/select() are implemented completely
> > within the application.   Such an approach allows us to potentially
> > supply specialized implementations of services on a resource by 
> > resource
> > basis.
>
> Is this a Linux emulator ? Something that might be kind of interesting
> is the possiblity of borrowing code from each project for implementing
> a Linux emulator. How complete are your Posix threading semantics ? 
> just
> curious again about corner cases. :) Those things have been a classic
> killer in Solaris and other M:N threading systems.

It has linux binary compatibility in with its features so I guess yeah 
it is.

Thread scheduling seems to be a bit of an art vs science thing :)

> Thanks
>
> bill