Re: Hi, and embedded routers
+++ David N. Welton [04-07-12 12:50 +0200]:
> >>busybox is by it's very nature something that you would want to
> >>recompile to make sure you have only those things that you need, no?
> Another thing that is in my mind with regards to an embedded Debian
> system is: how to keep my customized version in sync with new debian
> packages? Of course, at a certain point, you're likely to just grab
> certain versions and stick with them, at some point in the future you
> may wish to update, and at that point you need to keep track of and
> merge your changes.
This is a real issue for making this useful to people. I'm currently using
open embedded a lot and this is one thing it does really well.
Essentially emdebian needs a 'build world' scheme, and that scheme needs to
be able to patch packages with local changes before/during the build.
This isn't something we have worried too much about yet as we have a whole
load of more basic things to sort first.
One way of doing this might be to use OE to do this, but there may be a
simpler way. (oe+stag could get very complicated, and we might be better
off not trying to mix the two worlds up).
> >>I think a good embedded system based on Debian would take this need to
> >>recompile into account. From the web site and docs, I don't really know
> >>what emdebian does, if anything.
Yes, it is a bit vague. The recent update should improve things a bit, but
there is still much room for improvement.
> >Also look at buildd.emdebian.org and stag.mind.be for more info. The main
> >emdebian page is not updated yet.
> I looked at those... I don't know, there is something that doesn't
> convince me a lot. It seems like you have to do an awful lot of little
> steps by hand. Almost to the point where one begins to wonder what the
> point is, and why one isn't just compiling by hand... I'm sorry I can't
> be more specific, but it's just a general feeling I get from looking at
> the stag docs. Maybe it would all seem much clearer were I able to look
> over your shoulder.
Currently we are working on the mechanisms and tools to cross-build small
debian. One thing that is currently missing is target-side dependency
management, which it seems to me is something we do need to do to make this
really useful, so you can say 'build image' and it goes off and does
everything needed. This will require some changes to debian packages to
distinguish between build dependencies which need to be on the target and
build-dpes that need to be on the host. A hueristic should get this right
most of the time, but that may not be sufficient...
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