ubuntu - How can I specify the repository from which a package will be installed? (emacs-snapshot) - Super User

You can specify a repository with -t option. As an example, I have added the following repository to /etc/apt/sources.list to install Iceweasel latest release:
deb http://mozilla.debian.net/ squeeze-backports iceweasel-release
As you know there is a same package iceweasel in the official Debian repository. If I want install Iceweasel from this specific repo I run:

apt-get install -t squeeze-backports iceweasel

I found a workaround. First I needed to find the repositories that had the pacakage:

$ apt-cache showpkg emacs-snapshot
Package: emacs-snapshot
Versions: 
1:20100111-1~lenny1 (/var/lib/apt/lists/emacs.orebokech.com_dists_lenny_main_binary-amd64_Packages) (/var/lib/dpkg/status)
 Description Language: 
                 File: /var/lib/apt/lists/emacs.orebokech.com_dists_lenny_main_binary-amd64_Packages
                  MD5: 906df684c212eabe267e6b5c2e8c2032

1:20090909-1 (/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_karmic_universe_binary-amd64_Packages)
 Description Language: 
                 File: /var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_karmic_universe_binary-amd64_Packages
                  MD5: 906df684c212eabe267e6b5c2e8c2032


Reverse Depends: ...
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In the Versions: section. I see the versions that come from different repositories:

• 1:20100111-1~lenny1
• 1:20090909-1

So now we just tell apt or aptitude to install that specific version:

$ sudo aptitude install emacs-snapshot=1:20100111-1~lenny1

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