[p2-dev] I'm lost. "Could not locate the running profile instance" - how

[Marc Weber <marco-oweber@xxxxxx>]

In case I'm totally off topic can you point me into the right direction?

My goal: enhancing Eclipse support on NixOS. NixOS is linux distribution
based on the nix package manager. (www.nixos.org).
It differs from debian in one way:

debian install everything into /usr/bin/* or such whereas NixOS
let's you install different versions of the same package into
/nix/store/hash-package-name/usr/bin

multiple /nix/store/hash-name paths are joined to form a user
environment.

So basicaly there are two options

a) Make the package manager be aware of all Eclipse plugins and use 
  link files "path=c:\example\XYZFeature" to create the final set of
  plugins loaded into plugins
  + Because of nix you can always rollback instantly
  - I'd have to duplicate the dependency analysis code and include that
    into the package manager or make p2 export such a list of
    dependencies.

b) Copy the whole eclipse installation directory to a user directory and
use that.

  Howeever doing so I ran into the
  ProvSDKUIActivator.ANY_PROFILE = false;
  issue beeing described on http://wiki.eclipse.org/Equinox_p2_Getting_Started
  Setting it this to true makes the gui appear however the pluigns don't
  appear p2 having downloaded them?

  I'm also not sure what a "self hosted workbench" is ?

I prefer b) over a because it would be a less work.

Could not locate the running profile instance. The eclipse.p2.data.area
and eclipse.p2.profile properties may not be set correctly in this
application's config.ini file

Does some internal documentation exist explaining what a p2 profile is?
I've tried browsing the code to see when a profile is created and what
it is. But I'm still totally lost.

I've found that I can set
eclipse.p2.data.area
eclipse.p2.profile

But I don't know what to provide here?
Anyway eclipse.p2.data.area defaults to some writable path within the eclipse
directory, doesn't it?

I've also seen that there is an attempt to adress these linux
distribution specific issues:
http://www.eclipse.org/proposals/linux-distro/
Do you know how to get in touch with those people?

I'd be glad if you just could tell me RTFM and point me to the resources
to make p2 work in any way.

Thank you
Marc Weber