Skip to Content.
Sympa Menu

sm-users - Re: [SM-Users] menuconfig for casts

sm-users AT lists.ibiblio.org

Subject: Sourcemage Users List

List archive

Chronological Thread  
  • From: Arthur Nascimento <tureba AT gmail.com>
  • To: sm-users AT lists.ibiblio.org
  • Subject: Re: [SM-Users] menuconfig for casts
  • Date: Fri, 16 Dec 2005 17:58:54 -0200

Hi!
May I join this conversation? Since nobody else is joining I thought I
could make myself an example and bring other lurkers into the chat.

2005/12/16, Thomas Orgis <thomas-forum AT orgis.org>:
> But still I have to watch out for the question I want to answer differently
> (pressed enter one time too much: redo it again)... and there are these
> answers that are remembered in a way that I cannot change them (question
> and answer appearing in []brackets without a prompt) - The rule behind them
> is not so clear to me. Of course, I could look at the code to find it...

I agree with Thomas on every aspect so far: answering to the very same
question a second time (or more) is definately a pain. I remember the
last time I tried to install SMGL, on the initial rebuild, I had to
answer 3 or 4 times if I wanted to cast gettext. Seems simple enough,
since it stops there, but it is a real pain to reconfigure xorg over
and over again because of so many programs depending on it.
Also, there are those questions that just go by automatically answered
and all I can do is restart the cast asking it to force reconfigure.
This could be so easy with a menuconfig-like thingy to help.

>
> > I'll point out that backing up after you answer a question isnt really
> > a trivial thing to do in a robust and efficient way. Theres a lot more
>
> I didn't say that it is trivial... just that it seems desirable for
> error-prone humans;-)

Very much desirable for me. Yet, not trivial, that's for sure.

>
> > going on then whats just presented to the end user. All relavent spell
> > files are shell scripts in a turing complete language, theres not really
>
> Wait. Yes, I already noted that spells consist of shell scripts... but are
> they really allowed to do everything? Could a spell config script do `rm -f
> /boot/*` ? I'd think that spell scripts (apart from install) should only
> (be able to) access system information in a read-only way and store their
> config/do their compilation in a confined place. And besides what is
> allowed for them to do, what is possible in reality? Can one guarantee a
> certain set of commands to be available to the scripts (sed, perl, ...)
> even on a very, very minimal system? How far does the turing completeness
> go in reality?

If I may be so bold, I am quite sure Andrew doesn't really mean
turing-complete. We all know very well what turing completeness means
and what a universal turing machine is. I know we all are or have been
computer science or mathematics students, but I will remind us what
those things mean. A system is turing-complete if it can behave as an
UTM. UTM is a machine that can do anything/everything (a computer, for
instance). That said, I am sure sorcery isn't turing-complete, and it
shouldn't be. Can it make complex graphics calculations, comet crash
simulations, play emulated console games, surf the web, work as a
server etc? We are not talking about SMGL, but about sorcery
(cast+scribe+...); SMGL is certantly turing-complete. On a smaller
scale, can rmdir make a dir? Can mkdir remove a dir? No, therefore
neither is turing-complete. But can a GNU system create or remove a
dir? Yes! Can it do those things that I asked about sorcery? Yes! The
important question: can it behave as any other turing machine? Yes,
therefore, it is a universal turing machine and is turing-complete.
On some small details sorcery is turing-complete, but not on all
points. For instance, it is necessary that the system has some sort of
construction that allows it to loop to be t-c (the requirement is that
it must be able to never halt, ie, reach an end). On that point almost
everything seems t-c, but it alone cannot be the decisive point to say
what is or is not turing-complete.
So to sum up, Thomas, everything has at least a little bit of turing
completeness but only complete systems able to work as a universal
turing machine are fully turing-complete. Besides, we all know that
theory and practice are very different. Real machines are never turing
machines and vice-versa so don't worry about any of this.
I may have deviated myself from the original goal, so returning to it:
I agree that some things are dangerous for sorcery to do. The most
dangerous is actually 'rm -rf /home/' since the user's data is usually
the most precious information. However, if the system is to be
updated, them the program needs full rwx permissions to all files. It
is only important to keep user files safe and have the option of
whether to update config files or not, which by the way, SMGL does
very well, I must add.

[...]
> OK, you have quite some points there... I still think that in principle the
> configuration could be done in a menuconfig-like way (on the look-and-feel
> side, not internally) for a whole cast together, but I see that the spell
> design would have to take care of being able to go back and forth, support
> enabling and disabling of things. So even if this could be done, it won't
> be done in the near future.

Some menuconfig-like way of doing thing seems very good, but I think
it goes against the flow of SMGL right now. As Andrew noted, SMGL is
proud of its dynamicity, while the way you are suggesting (and that I
support) would need lots of things to be static, such as it is with
the actual kernel configs. The work will be huge to make the switch,
although I think it will be worth the while.

You must be thinking 'who is this?' I have to say that I know little
of how SMGL works internally (I only know c, c++, python and a few
others, but I suck at bash scripting) but I can try to contribute with
theory and algorythms (which is possibly to become the thesis of my
major). So maybe some day I can send some idea to help.
Moreover, I have tried to install SMGL 4 or 5 times in the past and I
never get it finished because of some compile errors in various places
(every time in a different place, even though I use only the stable
grimoire), so I end up always going back to my FC to be able to do my
work. So I know a lot about the frustration Thomas feels.
I lurk in this mailing list just waiting for some change that will
make SMGL work for me, and maybe this is it, maybe not. At every new
release I go ahead and test it, but I just don't have the time to try
and figure out the problems of the spells or to reconfigure things 2
or 3 times on the same cast. I wish I did. (That is my excuse for
never helping you guys: time.) I just need a system that works well
and possibly that is optimized for my machine, but LFS&DIY are way too
simple and crude, Gentoo is overly difficult to install and SMGL
simply hasn't worked for me yet - so I give up the optimization and
stay with FC.

Thanks for your time. Maybe next time I might be of more help.
Arthur



Archive powered by MHonArc 2.6.24.

Top of Page