Datasheet

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Part I ✦ The Fundamentals
kword? You can temporarily override your pinning preferences with apt-get’s --
target-release
option (synonyms are -t and --default-release):
# apt-get install -t testing kword
Another method, which is handy if you are installing packages from multiple distri-
butions in the same install session, looks like this:
# apt-get install kdelibs4 kword/testing kdm
In this case, kdelibs4 and kdm will come from stable, while only kword will come
from testing.
These methods can be used to remove packages too.
Installing from a specific site
The origin variant of the pin field in /etc/apt/preferences can be used to
ensure packages have a higher priority if they come from a particular place. Use a
stanza like this:
Explanation: packages from my own site
Package: *
Pin: origin “src.braincells.com”
Pin-Priority: 999
Installing (or keeping) a specific version
Sometimes you might want to ensure that a package doesn’t get upgraded. Maybe
you have a local package that you’ve tweaked and don’t want overwritten with a
generic version. Or maybe you are relying on the functionality of one particular ver-
sion of the package. Again, pinning can help. This time the
version variant of the
pin field is used. A specific package name is also used:
Explanation: bash 2.* only
Package: bash
Pin: version 2.*
Pin-Priority: 999
This allows upgrades of any new 2.* versions of the bash shell, but it keeps you
from any nasty surprises when
bash 3 comes out. (This is just an example. Usually
in Debian, packages that are significantly different from their earlier versions are
given different names, such as bash 3.) Note that the comparison of version num-
bers is done alphabetically, not numerically.
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