APT /etc/apt/preferences

       sources.list(5)  (stable testing )    APT  apt-get   APT APT

       sources.list(5)   apt-get sources.list(5)  APT

   APT
             apt-get  APT /etc/apt/apt.conf

          apt-get install -t testing some-package



          APT::Default-Release "stable";


       APT

        100
          ()

        500


        990


        APT  100   500

       APT

       o   1000   (  APT  1000   )

       o

       o    ()

       o   --reinstall


         ( 100) sources.list(5)  ( 500  990) apt-get install some-package
       apt-get upgrade

        apt-get install some-package apt-get upgrade

        apt-get install some-package apt-get upgrade

   APT
       APT

       o   ("Pin-Priority")   ()   "5.8" perl

        "unstable"

          Package: *
          Pin: release a=unstable
          Pin-Priority: 50

        "stable"   "3.0"

          Package: *
          Pin: release a=stable, v=3.0
          Pin-Priority: 500


   APT
       APT  (P)   ()

       P > 1000


       990 < P <=1000


       500 < P <=990


       100 < P <=500


       0 < P <=100


       P < 0




       APT

          Package: perl
          Pin: version 5.8*
          Pin-Priority: 1001

          Package: *
          Pin: origin ""
          Pin-Priority: 999

          Package: *
          Pin: release unstable
          Pin-Priority: 50



       Package:


       Version:


       Release .../dists/dist-name .../dists/stable/Release,
       .../dists/woody/Release    1 Packages Release   APT

       Archive:
            "Archive: stable" Release stable  APT

             Pin: release a=stable

       Version:
            GNU/Linux  3.0 testing unstable   APT

             Pin: release v=3.0
             Pin: release a=stable, v=3.0
             Pin: release 3.0

       Component:
          Release   "Component: main" main  (Debian )  APT

             Pin: release c=main

       Origin:
          Release  Debian  APT

             Pin: release o=Debian

       Label:
          Release Debian  APT

             Pin: release l=Debian

       sources.list(5) Packages Release /var/lib/apt/lists apt.conf
       Dir::State::Lists
       debian.lcs.mit.edu_debian_dists_unstable_contrib_binary-i386_Release
       debian.lcs.mit.edu unstable contrib binary-i386 Release

   APT
       APT Explanation:

       APT Pin-Priority:  Pin-Priority: release ...   (1)



        APT stable   (500) Debian

          Explanation: Uninstall or do not install any Debian-originated
          apt-get dist-upgrade


        testing

          apt-get install package/testing



        APT testing unstable Debian

          Package: *
          Pin: release a=testing
          Pin-Priority: 900

          Package: *
          Pin: release a=unstable
          Pin-Priority: 800

          Package: *
          Pin: release o=Debian
          Pin-Priority: -10


        sources.list(5) testing

          apt-get install package-name
          apt-get upgrade
          apt-get dist-upgrade


        unstable  apt-get upgrade testing testing unstable unstable

          apt-get install package/unstable



       apt-get(8) apt-cache(8) apt.conf(5) sources.list(5)


       [1]APT   APT /usr/share/doc/debian/bug-reporting.txt reportbug(1)


        <nabetaro@debian.or.jp> (2003-2006), Debian JP Documentation ML
       <debian-doc@debian.or.jp>

AUTHOR

       APT team
          Author.

REFERENCES

       1. APT