February 1998
- OT: Following in the footsteps of JCL Alex Oren
- OT: Following in the footsteps of JCL Nathan Yospe
- OT: Following in the footsteps of JCL Richard Woolcock
- OT: Following in the footsteps of JCL Chris Gray
- OT: Following in the footsteps of JCL coder@ibm.net
- OT: Following in the footsteps of JCL Marc Eyrignoux
- Ada? Andrew C.M. McClintock
- Monthly FAQ posting Koster, Raph
- Monthly FAQ posting Adam Wiggins
- Monthly FAQ posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Chris Gray
- Monthly FAQ Posting Ling
- Monthly FAQ Posting J C Lawrence
- Monthly FAQ Posting J C Lawrence
- Monthly FAQ Posting Alex Oren
- Monthly FAQ Posting Greg Miller
- Monthly FAQ Posting s001gmu@nova.wright.edu
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling
- Monthly FAQ Posting Ling Lo
- Monthly FAQ Posting Koster, Raph
- Monthly FAQ Posting Ling Lo
- Monthly FAQ Posting Greg Miller
- Monthly FAQ Posting Marian Griffith
- Monthly FAQ Posting Greg Miller
- Monthly FAQ Posting Ling Lo
- Databases Shawn Halpenny
- OT: This is a test coder@ibm.net
- OT: This is a test Alex Oren
- Clients and things [Was: OT: This is a test] Matt Chatterley
- Clients and things [Was: OT: This is a test] coder@ibm.net
- Clients and things [Was: OT: This is a test] Matt Chatterley
- MUD Development Digest Dr. Cat
- DBs and Events Greg Munt
- DBs and Events Nathan Yospe
- DBs and Events Greg Munt
- DBs and Events Nathan Yospe
- DBs and Events Felix A. Croes
- DBs and Events Jon A. Lambert
- DBs and Events coder@ibm.net
- DBs and Events s001gmu@nova.wright.edu
- DBs and Events Jon A. Lambert
- DBs and Events coder@ibm.net
- (subject missing) Ben Greear
- META: Unsubscribed users dur to bounces coder@ibm.net
- META: Unsubscribed users dur to bounces Adam Wiggins
- Source Code Release Greg Munt
- Source Code Release Ben Greear
- Source Code Release Greg Munt
- Source Code Release Ben Greear
- Source Code Release Greg Munt
- Source Code Release Richard Woolcock
- Source Code Release Ben Greear
- Source Code Release Chris Gray
- Source Code Release Greg Munt
- Source Code Release coder@ibm.net
- Source Code Release Richard Woolcock
- Source Code Release Stephen Zepp
- Source Code Release Jon A. Lambert
- Source Code Release Greg Munt
- Source Code Release Jon A. Lambert
- Source Code Release Greg Munt
- Source Code Release Travis Casey
- Source Code Release Jon A. Lambert
- Source Code Release Jon A. Lambert
- [RESEARCH]MUD articles archive (fwd) Greg Munt
- Socket programming (Was: The impact of the web on muds) Jon Leonard
- Socket programming (was: The impact of the web on muds) Vadim Tkachenko
- Socket programming (was: The impact of the web on muds) Richard Woolcock
- byte-code anyone? Chris Gray
- byte-code anyone? Jon Leonard
- byte-code anyone? Chris Gray
- byte-code anyone? Jon Leonard
- byte-code anyone? Chris Gray
- user-centered design (was Clients) Mike Sellers
- OT: Linux g++ Greg Munt
- OT: Linux g++ Ben Greear
- OT: Linux g++ coder@ibm.net
- OT: Linux g++ Shawn Halpenny
- OT: Linux g++ Chris Gray
- OT: Clients Vadim Tkachenko
- OT: Clients Adam Wiggins
- OT: Clients coder@ibm.net
- META: OS wars coder@ibm.net
- META: OS wars Mike Sellers
- Clients Stephen Zepp
- Moore's Law sucks (was: 3D graphics) Brandon J. Rickman
- Moore's Law sucks (was: 3D graphics) Adam Wiggins
- Moore's Law sucks (was: 3D graphics) Chris Gray
- Moore's Law sucks (was: 3D graphics) coder@ibm.net
- Moore's Law sucks (was: 3D graphics) Brandon J. Rickman
- Moore's Law sucks (was: 3D graphics) Mike Sellers
- Moore's Law sucks (was: 3D graphics) Chris Gray
- Moore's Law sucks (was: 3D graphics) Ben Greear
- Moore's Law sucks (was: 3D graphics) Ling
- Moore's Law sucks (was: 3D graphics) Brandon J. Rickman
- Moore's Law sucks (was: 3D graphics) coder@ibm.net
- Moore's Law sucks (was: 3D graphics) Alex Oren
- Version Control (was: DBs and Events) Vadim Tkachenko
- Version Control (was: DBs and Events) coder@ibm.net
- Version Control (was: DBs and Events) Vadim Tkachenko
- Version Control (was: DBs and Events) coder@ibm.net
- Version Control (was: DBs and Events) coder@ibm.net
- Version Control (was: DBs and Events) Jon A. Lambert
- Version Control (was: DBs and Events) s001gmu@nova.wright.edu
- Version Control (was: DBs and Events) Raph & Kristen Koster
- Version Control (was: DBs and Events) coder@ibm.net
- Version Control (was: DBs and Events) Felix A. Croes
- Net protocols for MUDing (was: Moore's Law sucks) Jon Leonard
- Net protocols for MUDing (was: Moore's Law sucks) coder@ibm.net
- Net protocols for MUDing (was: Moore's Law sucks) s001gmu@nova.wright.edu
- Net protocols for MUDing (was: Moore's Law sucks) Vadim Tkachenko
- Net protocols for MUDing (was: Moore's Law sucks) Chris Gray
- Net protocols for MUDing (was: Moore's Law sucks) Caliban Tiresias Darklock
- Net protocols for MUDing (was: Moore's Law sucks) J C Lawrence
- Net protocols for MUDing (was: Moore's Law sucks) J C Lawrence
- Net protocols for MUDing (was: Moore's Law sucks) Adam Wiggins
- Net protocols for MUDing (was: Moore's Law sucks) Chris Gray
- Net protocols for MUDing (was: Moore's Law sucks) Vadim Tkachenko
- Net protocols for MUDing (was: Moore's Law sucks) Chris Gray
- Net protocols for MUDing (was: Moore's Law sucks) Vadim Tkachenko
- Net protocols for MUDing (was: Moore's Law sucks) Chris Gray
- Net protocols for MUDing (was: Moore's Law sucks) Adam Wiggins
- Net protocols for MUDing (was: Moore's Law sucks) Chris Gray
- Net protocols for MUDing (was: Moore's Law sucks) J C Lawrence
- Net protocols for MUDing (was: Moore's Law sucks) Chris Gray
- Net protocols for MUDing (was: Moore's Law sucks) Adam Wiggins
- Net protocols for MUDing (was: Moore's Law sucks) Ben Greear
- Net protocols for MUDing (was: Moore's Law sucks) Adam Wiggins
- Net protocols for MUDing (was: Moore's Law sucks) s001gmu@nova.wright.edu
- Net protocols for MUDing (was: Moore's Law sucks) Jon A. Lambert
- Net protocols for MUDing (was: Moore's Law sucks) J C Lawrence
- VEIL (was: Clients) Brandon Gillespie
- LDMs (large dynamic maps) was Unique items Mike Sellers
- Describing the environment Stephen Zepp
- Describing the environment Richard Woolcock
- Back on the list Niklas Elmqvist
- Back on the list Chris Gray
- Back on the list coder@ibm.net
- Unique items The Eternal City
- Unique items coder@ibm.net
- Position sorting Adam Wiggins
- Position sorting coder@ibm.net
- Unique items coder@ibm.net
- Unique items Nathan F Yospe
- BOOK: Myer's Silverlock coder@ibm.net
- BOOK: Myer's Silverlock Chris Gray
- BOOK: Myer's Silverlock Adam Wiggins
- Dynamic Loading of Modules (was: Back on the list) Niklas Elmqvist
- Dynamic Loading of Modules (was: Back on the list) Vadim Tkachenko
Niklas Elmqvist wrote:
>
> On Mon, 23 Feb 1998 coder@ibm.net wrote:
> > On 20/02/98 at 12:43 AM, Niklas Elmqvist <d97elm@dtek.chalmers.se> said:
> > >Nothing sensational,
> > >it's all been done before, but I could outline my little scheme here if
> > >there is interest.
> >
> > Please do.
>
> Okay, here goes...
>
> As I said earlier, I am aiming to decouple the actual core server from
> the world processing routines. Ideally, the main server would not even
> *know* it is running a MUD, it would be sort of a general-purpose core,
> and all the functionality such as DB management, socket I/O and AI would
> be implemented in free-standing modules separate from the main executable
> (at least, I envisioned this in the beginning). I mentioned this to a RL
> friend of mine, and he pointed out that it all sounded very much like
> conventional OS architecture, especially like the module system of Linux
> kernels. I studied these a bit and learned some good stuff about dynamic
> loading (or linking), and then started experimenting with using DL
> together with C++. The results can be found at
> <URL:http://artoo.hemmet.s-hem.chalmers.se/~crozius/resources.html>, but I
> will outline it briefly here as well.
>
> In essence, what I discovered (to myself, that is, this is no doubt old
> news to some people) was that I could compile the core server with a base
> class with very little functionality, call it aClass, which called a
> factory function in a shared library, returning a pointer to an aClass
> object. Then, in the actual shared library (which is linked in with the
> main binary at run-time) I instead return an instance of a class
> called bClass, which inherits from aClass but which is totally unknown to
> the core server. Best of all, it works! That is, when I call the Execute()
> member function on the aClass handle in the core (which, unbeknowst to the
> core, points to a bClass object with redefined Execute() function), the
> correct Execute() function is called, that is bClass::Execute().
>
> Now, if aClass and bClass had been part of the same binary, I would not
> have been surprised. In fact, as you probably all know, this is called
> late binding in the O-O community and is an important feature of all
> serious O-O languages. However, what surprised and delighted me is that
> late binding *still* works even though the core and shared lib described
> above are separately compiled, and the bClass is totally unknown to the
> core! In my eyes, this is the ultimate test of late binding, and G++
> pulled it off nicely! Incidentally, a friend (the one mentioned above)
> later reported that this is impossible in Windows-style DLLs.
>
> If you are wondering what the fuss is all about (or why this posting is
> getting so long), let me just say this: One application of this could be
> an Event class (in an event-driven system), whose base class is known to
> the core server (allowing for it to check the priority and expiration of
> the event, among other things), while the modules can inherit from the
> base class and redefine it to suit their particular needs. I also plan on
> using this technique for Handler objects which take care of things such as
> socket I/O, parsing, DB managment, etc, and the good thing about it is
> that I thus will be able to attach and detach the modules at run-time (to
> remedy a bug, for example). If the base classes are correctly implemented,
> the core will never even have to be recompiled and thus never rebooted
> (not accounting for fatal bugs, that is <g>)!
Not quite so.
See, I use almost exactly the same technique in my Java development,
and indeed, it's possible, using Class.forName( ... ), instantiate the
absolutely unknown before classes - in fact, I suspect that the other
guy, who lives at http://www.wwwalker.com/, used this technique to
produce applets at least a year ago, but his technique seems to be even
more pervert - he compiles classes on-demand, and then actually loads
them.
The weak point for me is that once you load the class, it's extremely
difficult to UNLOAD it.
I've heard that the guys who write the servlet support for Apache
managed to write the custom ClassLoader to do that, but didn't have time
to dig it myself.
How do you handle this?
> Whew. Sorry if I babbled on a mite too much, but I hope this will be of
> some use to someone.
I really like this way too.
> -- Niklas Elmqvist (d97elm@dtek.chalmers.se) ----------------------
--
Still alive and smile stays on,
Vadim Tkachenko <VadimT@4CS.Com>
--
UNIX _is_ user friendly, he's just very picky about who his friends are - Dynamic Loading of Modules (was: Back on the list) J C Lawrence
- Dynamic Loading of Modules (was: Back on the list Jon A. Lambert
- Dynamic Loading of Modules (was: Back on the list) Vadim Tkachenko
- Net protocols for MUDing s001gmu@nova.wright.edu
- Net protocols for MUDing Stephen Zepp
- Net protocols for MUDing Chris Gray
- Net protocols for MUDing Adam Wiggins
- Net protocols for MUDing J C Lawrence
- Net protocols for MUDing Shawn Halpenny
- Net protocols for MUDing J C Lawrence
- Net protocols for MUDing Chris Gray
- Dynamic Loading of Modules Niklas Elmqvist
- Senses (was: The MLI Project) s001gmu@nova.wright.edu
- bar-time (was The MLI Project) Mike Sellers
- 3D engines for MUDs (was: The MLI Project) Niklas Elmqvist
- 3D engines for MUDs (was: The MLI Project) J C Lawrence
- 3D engines for MUDs (was: The MLI Project) Michael Hohensee
- 3D engines for MUDs (was: The MLI Project) Miroslav Silovic
- 3D engines for MUDs (was: The MLI Project) Michael Hohensee
- Why not compile java into object code? Ben Greear
- Why not compile java into object code? Cynbe ru Taren
- Why not compile java into object code? Caliban Tiresias Darklock
- Why not compile java into object code? Nathan F Yospe
- Why not compile java into object code? Niklas Elmqvist
- Why not compile java into object code? Ben Greear
- Why not compile java into object code? Jon A. Lambert
- Why not compile java into object code? Travis Casey
- Why not compile java into object code? Chris Gray
- Tutorial: Comments on Hand-crafting a compiler Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part I: Introduction Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part II: Expression Parsing Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part I: Introductio Chris Gray
- Tutorial: Let's build a Compiler! - Part I: Introductio s001gmu@nova.wright.edu
- Tutorial: Let's build a Compiler! - Part I: Introductio coder@ibm.net
- MUD Development Digest Dr. Cat
- MUD Development Digest Koster, Raph
- MUD Development Digest Mike Sellers
- Tutorial: Let's build a Compiler! - Part III: More Expressions Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part IV: Interpreters Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part V: Control Constructs Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part VI: Boolean Expressions Jon A. Lambert
- Tutorial: Let's build a Compiler! - Comments Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part VII: Lexical Scanning Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part VIII: A Little Philosophy Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part IX: A Top View Jon A. Lambert
- Tutorial: Let's build a Compiler! - Part X: Introducing TINY Jon A. Lambert
- Compilers: Toy available for ftp Chris Gray