Working with portage is quite a hassle at times - it really depends on what you are needing as to what you will have to do.

For example, if you are using old packages (outdated system), and there are many updates available, you may have to update many packages in order to satasify dependencies. Often it is good to limit the package that is allowed to be used by using "/etc/portage/package.mask" if you are happy with your current build, and upgrade as necessary.

Sometimes you will emerge something, and it will build and install properly, and other times there will be an error.

Often you will need to unmask a package in order to build it in, and you WILL NOT want these packages to be reemerged if you were to "emerge world" in the future - the package will remain on the system, but will not re-emerge.

Therefore there's the "--oneshot", or "-1" flag.


A good example for this, as of today anyhoo (12/18/2009), is emerging "gnome-system-tools" (hard masked, and arch masked), and I will show the difference with ntp-client (no mask).

First off, use etc/portage/package.keywords to tell the system it is allowed to be installed (even though it's masked).

Then, use /etc/portage/package.unmask to tell your system which version is allowed to be installed.

Therefore, I assume you will have a list of applications you use in your package.keywords, such as:

vi /etc/portage/package.keywords

In package.unmask, you will require the same as, or similar to the following (apparently this will depend on portage, this is what I decided to use):

vi /etc/portage/package.unmask

Then you can emerge what you need:

Emerge gnome-system-tools liboobs oneshot accepting ~x86 packages without building in samba support


In the command, there are a few things that are being done.

First:

This is being used to prevent us from screwing anything up by allowing the emergence of packages that are being tested - globally.

--This is merely allowing us to emerge "~x86" packages for only what is being emerged.

-- Since we are limiting the versions of these packages as it is using the "package.unmask", it should be apparent as to what will be emerged, and from what tree (stable {no mask} or tested {masked}).
-- now we could just add the "~x86" flag to package.unmask, such asbut I do not want to allow this because I do not want to continue to use testing packages once a stable release is unmasked (in otherwords, I want to prevent this from being emerged automatically - I can manually remove the unmask, and keywords once this have been marked as stable).

Second:

This is being done because apparently the package "dev-libs/liboobs" has issues with samba at the moment.
-- Since my /etc/make.conf includes samba, I have to manually remove this from being built in to prevent known build errors.

Third:

This will allow the following:
Emerge
-p == --pretend (Let's see what portage wants to do first)
-1 == --oneshot (do not add package to world file as it's being tested)
-N == --newuse (I recently modified my use flags in /etc/make.conf)
-v == --verbose (I like to see what's going on)
gnome-system-tools & liboobs


Make it live on boot:


Depending on how updated your system is, there may be several packages included for the install.

If you notice the packages that are wanting to be built in all are "~x86" packages, you may want to install stable builds for what you can, then install testing packages as needed.



emerge ntp:

--The first line will emerge ntp-client, related packages (dependencies).
--The second line will copy the sample config to the proper location.
--The third line will start the service on boot.