(hopefully I'm at the correct address here ;))
emerge -De system --start-from gnome-base/orbit
Does the same as "emerge -De system" but begins with 'orbit' and then emerges what had followed (assuming, all packages that should be merged in before, are already merged successfully).
I was doing an emerge -De system (~270 pkgs) and it hung at orbit (~30 pkgs left). But after emerging orbit, a resume was not possible anymore. So I had to use a ruby-script, posted in the forums, to continue without having to restart all over again.
But the script has some pitfalls
( http://forums.gentoo.org/viewtopic-t-422261-view-previous.html ),
so I wouldn't recommend it to 'normal users'. Such a --start-from option would be very nice. Also it would be possible to call
emerge -D progA progB progC --start-with bar/foo
Assume you wanted to emerge these three programs. Each has several dependencies itself. In the middle the emerge hangs due to some error. You could fix it and just call the same emerge command with --start-from to continue without any problems.
'resume' is a very nice option I always looked for some years ago, but a --start-from would be absolutely perfect! :)
I am not used to perl, so I cannot send a patch. :(
But I hope someone will find this option as useful as I do and implements it. :)
(sorry for my bad English)
emerge pkgA pkgB pkgC pkgD --start-with pkgD
pkgD depends on pkgC depends on pkgB depends on pkgA.
What do we do in this case, and how do we validate the dependency graph that you just cut in half with your --start-with <package>, in a general case.
Another thing that the new resolver may be able to do, definately not soon though.
> emerge pkgA pkgB pkgC pkgD --start-with pkgD
> pkgD depends on pkgC depends on pkgB depends on pkgA.
> What do we do in this case[...]
In this case "emerge pkgA pkgB pkgC pkgD" would emerge the packages in the following order:
so an "emerge pkgA pkgB pkgC pkgD --start-with pkgD" would start with:
Means: It just emerges pkgD, assuming A,B,C are already successfully merged and that's it. :)
*** Bug 110308 has been marked as a duplicate of this bug. ***
*** Bug 134500 has been marked as a duplicate of this bug. ***
Let's generalize a bit:
I think what you really want is a more convenient way to exclude some packages from a list of packages to be acted upon in general, not just --start-from. So what we're really after is a more powerful selecting mechanism. --ask seems to be the right place for this, a bit more interactivity then just yes/no wouldn't hurt it IMO.
*** This bug has been marked as a duplicate of bug 16342 ***