NAME

       apt-forktracer - a utility for managing package versions

SYNOPSIS

       apt-forktracer [ -v ]

DESCRIPTION

   Background
       Maintaining  Debian  stable systems sometimes requires installation of unofficial versions
       of packages:

       backporting newer versions
              This is necessary, when significant new functionality is required on the system but
              unavailable  in  the  official version found in the current stable release. In this
              case, the version string usually sorts as newer than the  official  stable  version
              string.  This  means that pinning is not necessary, as APT will select such package
              version by default.

       local changes to the official version
              Usually these are small changes, so a minor modification  of  the  package  version
              string is sufficient. There are two ways to do this:

              Try  to invent a version string newer than the current one, but older than the next
              official one.  This way does not require pinning, but is difficult to do  reliably.
              It  might  turn  out,  that  the next official version string is older than the one
              invented by you, which would cause the official version to be silently ignored.

              The other way is to modify the version string in such way that it  sorts  as  older
              than  the  official  one.   The  tilde  character is very useful here, because dpkg
              treats it in a special way: it is sufficient to append any string starting with the
              tilde, to the version string, e.g.  1.2 → 1.2~sl.1.  This requires you to "pin" the
              package to that version, but it is more reliable, because works regardless of  what
              the next official version number will be.

       In  both  cases, there is one major drawback: APT will not warn you when newer versions of
       official packages (point releases, security updates) will appear in  the  stable  release.
       This means you may miss some important change.

       apt-forktracer's job let you track newer official versions of locally overridden packages.

   Official package version definition
       Official  package  version  is  a  version which is available from a source, whose Release
       file's Origin header value is equal to the system distributor identifier, as indicated  by
       the lsb_release --id command, or by the DISTRIB_ID field in the /etc/lsb-release file.

   Program operation
       apt-forktracer  analyzes  each  installed  package  separately,  reporting on the standard
       output these packages which are in  a  "non-standard"  state.  What  "non-standard"  means
       depends on the mode of program operation:

       default (non-verbose) mode
              this  state  means  packages  in  an incorrect state (e.g. no candidate version) or
              packages whose candidate version is different than the  newest  available  official
              version.

       verbose mode
              this  state  also  includes  packages whose installed version is different from the
              candidate version

       In the default mode the program also reads configuration files, which let you ignore  some
       of  the  "non-standard"  packages,  as long as they meet certain criteria.  If there is no
       configuration for a given package, then a default configuration is used.  More information
       is available in forktracer.conf(5).

   Message format
       The program outputs messages such as the following:

           foobar (1.2.3->1.2.4) [Debian: 1.2.3 1.2.4] [Other origin: 1.2.2]

       Where:

       foobar package name

       1.2.3  installed package version

       1.2.4  candidate package version - see apt-cache(8).

       Debian the  value  of the "Origin" field of one of the package sources. Versions available
              from this source are listed after a colon.

       Other origin
              another source origin

OPTIONS

       -v     Turns on the verbose mode.

FILES

       /etc/apt/forktracer.conf
       /etc/apt/forktracer.d/*.conf

SEE ALSO

       forktracer.conf(5), apt_preferences(5), apt-cache(8).