Subject: Re: dynamic linker
To: NetBSD User's Discussion List <netbsd-users@NetBSD.ORG>
From: Arto Huusko <arto.huusko@utu.fi>
List: netbsd-users
Date: 03/20/2002 02:04:26
On 19-Maa-02, Greg wrote:

> [ On Tuesday, March 19, 2002 at 19:34:58 (+0000), Sean Witham wrote: ]
>> Subject: Re: dynamic linker
>> 
>> Has anyone done a good white paper on the pitfuls of 
>> dynamic linking ?
> 
> I've read some academic papers about the pitfalls of dynamic linking,
> and I know at least a few other software engineers who've hurled insults
> at every dynamic linking scheme they've ever run across.

I'm not very knowledgeable on the dynamic linking schemes on the *BSD,
or any other system with good memory protection and strong
process views (i.e. each process is its own virtual machine and no one
will disturb it), but somehow I can't help it but love the AmigaOS way
(and its a few good years since I developed any serious programs on Amiga).

The very fact that I had to bring my whole system down in order to
install new Mozilla+Galeon[3], which wanted newer PNG lib, which in
its turn required me to compile+install nearly all of GNOME et co.
Good God, is there something wrong with that, or is it just me?[4]

The Amiga library scheme is incredbile. So, it relies on
non-existent memory protection, but the stuff (and ease) it gives
to developer is simply awesome. I still think -- now that I know much more --
how funny it was/is that AmigaOS was bashed so much in the past, while
still being a *very* functional micro kernel system[1] (at the time
when everyone said micro kernels are the way to hell... hmm, I
guess people still say that).

At least Amiga libraries, in general, guaranteed one thing: they
gave you API and ABI, and it worked from 1985 to 199?, or, actually
2002. If something had to change, the library name (had to) changed,
not the just the version.


Hmm... what was my point? Oh, I guess I am just ranting, but
somehow I felt this was a necessary point to make. The recompilation
and installation of ~_everything_ made me a bit edgy[2]. And anyway,
the Amiga library system (and friends) is great.


[1] Mentioned also in the infamous Torvalds vs. Tanenbaum
debate (ancient). But no one had any reply... And Tanenbaum doesn't
even mention AmigaOS in his bible of OSs, which I thought a bit odd
(and I paid ee for the book to pass a course with a poor 2- grade :(

[2] Also the fact that my MSI board nearly blew up. I guess it
still will, but it works for now.

[3] And Galeon won't even compile now.

[4] I understand now the dreaded libc major rev bump.

-- 
Arto Huusko (arto.huusko@utu.fi) | Diving Is Fun
Divecalc @ http://divecalc.cjb.net