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From: evans@testmax.ZK3.DEC.COM (Marc Evans Ultrix Q/A)
Newsgroups: comp.windows.x
Subject: Re: extension philosophy [was Re: audio servers]
Message-ID: <6865@decvax.dec.com>
Date: 14 Mar 90 20:38:37 GMT
References: <780@auto-trol.UUCP> <776@auto-trol.UUCP> <9003121606.AA03191@expo.lcs.mit.edu> <4840@crltrx.crl.dec.com> <1837@mit-amt.MEDIA.MIT.EDU> <3015@bacchus.dec.com>
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In article <780@auto-trol.UUCP>, marbru@auto-trol.UUCP (Martin Brunecky)
writes:
> 
> 	The "big" extensions add a whole class of functionality.
> 	PEX, DisplayPostscript, XImage. The whole new dimension.
> 	Therefore, I would rather like to see such "extensions" as 
> 	specialized servers, activated where needed, living in
> 	separate address space. Since many extensions demand really
>         efficient access to the X server, sharing lots of X window
> 	semantics, they need an efficient, (shared memory based?),
> 	low level  server-to-server protocol. 
> 
What if the *big* extensions used a shared library mechanism (assuming that the
host OS supports the capability)? This would potentially eliminate most of the
concerns that I see you raising. An example of one implementation which
does this
is DECs' VMS X Server. It isn't often that I recommend looking at a VMS system,
but this is one thing that I think they have the right idea for.

I must admit that having a full threads implementation on top of MACH could be
real interresting, and would allow for some real flexability in the area of how
an extension is fastened into the X server. Is anybody out there trying to put
the server into the threaded and/or MACH environment?

- Marc
==========================================================================
Marc Evans - WB1GRH - evans@decvax.DEC.COM  | Synergytics    (603)893-8481
     Unix/X-window Software Contractor      | 3 Koper Ln, Pelham, NH 03076
==========================================================================