[JDEV] Server Platforms

[Paul Prince]

Tell me, why isn't Jabber already written with a modular design?  Shouldn't there
be a thread module to provide and abstract interface to the thread library,
elimination all of this?
-Paul

Benjamin Kahn wrote:

> On Mon, 12 Jun 2000, Eric Bowersox wrote:
>
> > >     1) Although cross-platformness is a great goal, pth
> > > doesn't really
> > > accomplish this.  (As your post shows.)
> >
> > It's good at being cross-platform between UNIX-alikes...and, since it's
> > FSF-owned code, I don't know how eager they are for it to be used on NT :-)
>
>         An argument could be made that most platforms HAVE thread
> libraries already.  And it could be said that POSIX threads are fairly
> standard, and it could be said that wrapper libraries can be created for
> platforms where POSIX threads are not available, or not the best
> choice.  In fact, these wrappers have been written for a number of other
> open source projects.
>
> > >     2) Pth takes over SIGUSR1 which is normally (?) used as
> > > a "reload
> > > configuration files" signal.
> >
> > It's usually SIGHUP that's used for reloading configuration files...however,
> > SIGUSR1 frequently has other "interesting" uses that, yes, pth would
> > preclude.
>
>         Good point.  I confused the signals.
>
> > >     3) Pth doesn't play nice when it gets near other threading
> > > systems.  This means that Jabber can not be linked with some
> > > libraries.  This limits the usefulness of Jabber in some cases.  (ODBC
> > > libraries are often linked with thread libraries.)
> >
> > Actually, pth provides a pthreads-compatible call interface, it looks like,
> > so this might not be the issue you think it is.  However, I can't say for
> > sure.
>
>         I looked this over.  The man page is interesting...   (7000+
> lines!)  It looks like PORTING an application from pthreads to pth might
> be an easy enough thing to do.  (Kind of.  It's hard to tell how well it
> works without trying it.)  However, this doesn't help if you are dealing
> with a library which you don't have the source to.  And some libraries you
> might not want to convert, and others ...  well, I admit it helps, but
> it's not a really GOOD solution.
>
> > >     4) Pth isn't used by a lot of other projects, so it might have
> > > hard to track down bugs.
> >
> > A few of which we've already seen :-).
> >
> > >     It has only one nice thing:
> > >     Pth is cooperative threading.  Cooperative means that most race
> > > conditions don't come up.  Switching to a non-cooperative thread model
> > > would be a lot of work as races get stamped out.
> >
> > True...you don't need things like mutexes as much in pth, although they're
> > provided.
>
>         Don't mind me.  I'm just upset because I'm trying to link in a
> commonly threaded library into Jabber.  I'll get over it.
>
>                                                 -Ben
>
> ------------------------------------ |\      _,,,--,,_  ,) ----------
> Benjamin Kahn                        /,`.-'`'   -,  ;-;;'
> (212) 924 - 2220 ext 201            |,4-  ) )-,_ ) /\
> ben at cybersites.com --------------- '---''(_/--' (_/-' ---------------
>         Q: Why does it crash?
>         A: Woah! You should have seen it last week!
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