Hi Piergiorgio,

On 04/26/11 18:10, Piergiorgio Beruto wrote:
> Hi,
> I'm an embedded sw developer already used to gentoo and portage.

Is your gentoo and portage usage already related to your embedded development?

> 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).

> 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.

> 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.

Then I'd try to fix crossdev to work within Gentoo Prefix, trying
to get identical output as on the vanilla Gentoo Linux system.

But I also would expect lots of work, resulting in patches for crossdev,
ebuilds/eclasses, as well as (prefix-)portage.

HTH,
/haubi/
-- 
Michael Haubenwallner
Gentoo on a different level