On Wed, 29 Aug 2001, Sheldon Hearn wrote:
> Here is Apache's list of platforms on which DSO (dynamic shared object)
> mechanism for loadable modules is supported:
>
> o Out-of-the-box supported platforms are:
> - Linux - SunOS - UnixWare - Darwin/Mac OS
> - FreeBSD - Solaris - AIX - OpenStep/Mach
> - OpenBSD - IRIX - SCO - DYNIX/ptx
> - NetBSD - HPUX - ReliantUNIX
> - BSDI - Digital Unix - DGUX
>
> o Entirely unsupported platforms are:
> - Ultrix
So that leaves the following Exim-supported systems unknown:
GNU/Hurd, HI-OSF (Hitachi), MIPS RISCOS, QNX. I don't suppose anybody is
actually using Exim on Ultrix any more.
> But I think if you're going to allow user-defined code, you should at
> least consider making that code dynamically loadable on platforms where
> it's easy to do so. Platforms on which this is not supported will be no
> worse off than if no loadable support were available at all. :-)
True. I worry, however, about the cost. Remember Exim doesn't just start
up and run. Its design requires it to be continually re-executed. Thus,
it would be doing additional loading a lot. Maybe someone will tell me
that it's all highly efficient and that machines are fast these days
anyway...
However, I saw a recent comment about StarOffice, which does a lot of
dynamic loading (I gather) and how slow it is to start up because of all
the function resolution that goes on.
Anyway, I've noted the point. I'm soon going to be at a stage where I
have to start making hard choices about what gets done for Exim 4.00,
and what gets left for later implementation. Stuff that isn't
incompatible with Exim 3 is more likely to get left (I want to get all
the incompatible changes over at once, if I can).
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.