2011/4/27 Michael Haubenwallner <email@example.com>:
> Hi Piergiorgio,
> On 04/26/11 18:10, Piergiorgio Beruto wrote:
>> I'm an embedded sw developer already used to gentoo and portage.
> Is your gentoo and portage usage already related to your embedded development?
Actually yes, I've been using Gentoo for several years for a wide
range of applications (both for my company and on my own) like
routers, L2 switches, servers, multimedia and desktop applications. In
fact I love gentoo because of its fexibility, like many other users
Embedded development used to be a different kind of beast, but at
company level the requirements for "big" embedded projects are the
same as for traditional development and I think it's the time to
enhance our ways of working to speed up our daily work and meet the
This is why I think portage might be a good solution: in embedded
development we're really missing a build system which allows you to
pick up traditional open source packages and your own packages
maximizing code reuse among projects. I believe portage has the degree
of modularity required, and since it's open source is much easier to
learn and to maintain.
>> I am wondering whether gentoo prefix could help me in the following: I
>> would like to use portage to cross compile some base linux packages
>> plus some board specific applications for a different number of boards
>> each requiring their own patches and packages, with a huge amount of
>> code to be shared among them.
> Basically yes, ...
>> I was lookong at crossdev but
> ... however I've not seen anyone trying to make crossdev working in Prefix.
> But I fail to see a reason for crossdev not to work in Prefix, even if
> I've not used crossdev myself. So IMO it just has To Be Done (tm).
Well, I've tried to have crossdev itself working in prefix and I
succeeded, the big problem was to cross-build the glibc, then I didnt
have the time to finish but maybe I could use some help?
>> the big problem is that I CAN'T get
>> administrative priviledges on the development machine, in fact each
>> user at the moment builds the packages in their own home.
> This is one of the reasons Gentoo Prefix was born.
>> To be more precise I wish I could use portage installed in my home
>> directory and have it use some cross-toolchain (either pre-built or
>> built through portage) to actually download, patch, configure, build
>> and install packages to some directory which will eventually be turned
>> into a target filesystem someway.
>> I've tried to use crossdev inside prefixed gentoo but failed to have
>> it working and I'm not sure it's the correct approach anyway.
> The special use case for Prefix here IMO is the combination of
> ROOT="/somewhere" with EPREFIX="" and non-Prefix profiles/keywords.
Yes, crossdev already uses the ROOT variable to specify the
installation path, I'm not yet very familiar with prefix related
variables so it might only be a matter of studying...
For instance what you mean exactly by "non-Prefix profiles/keywords"?
>> Have you guys any suggestion about my problem? That would save a lot
>> of users to keep developing new build systems and re-inventing the
>> wheel each time! Also they would never come to something as good and
>> featured as portage.
> For what I can say if I were in your situation:
> First, I'd try crossdev on some (virtualized) vanilla Gentoo Linux
> system, to see if crossdev /is/ the tool doing what I need, and to
> see how it works.
Yes, I'm already a crossdev user and I actually think it could be the
tool I am looking for, possibly with some tweaks.
> Then I'd try to fix crossdev to work within Gentoo Prefix, trying
> to get identical output as on the vanilla Gentoo Linux system.
That's the difficult part :)
> But I also would expect lots of work, resulting in patches for crossdev,
> ebuilds/eclasses, as well as (prefix-)portage.
That's what I am NOT familiar with, I am an experienced portage user
but not (yet) a good portage developer.
Maybe I could use a little help with this? Do you guys find this kind
of development useful/challenging? In which case, have you got a rough
idea about the effort in making a working prototype (your guess would
be much better then mine)?
Oh, one last thing: one of the big issues is about host machines... it
would be nice if the prefixed Gentoo could be portable across
different development machines / users. Do you think it's possible to
have a prefixed gentoo "relocatable"? I mean, I setup my prefixed
system, then i "tar cvj" the entire system then untar for a different
user / different machine, "change some config files / environment
variables" and have my prefixed system work without bootstrapping
Thank you very much for your time and help,
> Michael Haubenwallner
> Gentoo on a different level