NAME
germinate - expand dependencies in a list of seed packages
SYNOPSIS
germinate [-v] [-S source] [-s dist] [-m mirror] [-d dist,...] [-a arch]
[-c component,...] [-i] [--bzr] [--no-rdepends]
DESCRIPTION
germinate is a program to help with the maintenance of large software
distributions. It takes a list of seed packages and a mirror of the
distribution, and produces outputs with the seed packages and their
dependencies and build-dependencies expanded out in full.
Seeds
The contents of the Ubuntu distribution, and others, are managed by means
of seeds. At their simplest, these are lists of packages which are
considered important to have in the main component of the distribution,
without explicitly listing all their dependencies and build-dependencies.
Seed lists are typically divided up by category: a base or minimal seed
might list the core set of packages required to make the system run at
all, while a desktop seed might list the set of packages installed as
part of a default desktop installation. germinate takes these seeds,
adds their dependency trees, and produces an output for each seed which
contains a dependency-expanded list of package names. These outputs may
be handed on to archive maintenance or CD-building tools.
Some seeds may inherit from other seeds: they rely on those seeds to be
installed. For example, a desktop seed will typically inherit from a
minimal seed. germinate understands these inheritance relationships. If
a package in the desktop seed depends on ‘foo’, but ‘foo’ is already part
of the minimal seed or dependency list, then ‘foo’ will not be added to
the desktop output.
Seeds are stored in text files downloaded from a given URL. Lines not
beginning with ‘ * ’ (wiki-style list markup) are ignored.
Seed entries may simply consist of a package name, or may include any of
the following special syntax:
% Seed entries beginning with ‘%’ expand to all binaries from the
given source package.
[...] Seed entries may be followed with ‘ [arch1 arch2 ...]’ to
indicate that they should only be used on the given
architectures, or with ‘ [!arch1 !arch2 ...]’ to indicate that
they should not be used on the given architectures.
(...) Seed entries in parentheses indicate that the seed should be
treated as a recommendation of metapackages generated from this
seed, rather than as a dependency.
! Seed entries beginning with ‘!’ cause the given package to be
blacklisted from the given seed and any seeds from which it
inherits; this may be followed by ‘%’ as above to blacklist all
binaries from the given source package. Note that this may
result in uninstallable packages whose dependencies have been
blacklisted, so use this feature sparingly. The purpose of a
blacklist is to make it obvious when a package that is not
supposed to be installed ends up in germinate’s output, so that
package relationships can be fixed to stop that happening. It is
not intended for the purpose of working around buggy package
relationships, and attempts to do so will not work because apt
has no way to know about blacklist entries in seeds.
key: value
Some seeds also contain headers at the top of the file, in “key:
value” format. For the most part, these are not parsed by
germinate itself. The Ubuntu tasksel package uses keys beginning
with ‘Task-’ to define fields of similar names in its .desc
files. germinate-update-metapackage(1) uses some of these
headers to reduce the need for fragile configuration; see its
documentation for further details.
A STRUCTURE file alongside the seeds lists their inheritance
relationships. It may also include lines beginning with ‘include’,
causing other collections of seeds to be included as if they were part of
the collection currently being germinated, or lines beginning with
‘feature’, which set flags for the processing of seeds. The only flag
currently defined is ‘follow-recommends’, which causes germinate to treat
Recommends fields as if they were Depends. (Features may also be set on
a per-seed basis using lines beginning with ‘ * Feature:’ in the seed
file; here, ‘no-follow-recommends’ is also supported to allow Recommends-
following to be turned off for individual seeds.)
Build-dependencies and ‘supported’
There is typically no need for a default desktop installation to contain
all the compilers and development libraries needed to build itself from
source; if nothing else, it would consume much more space. Nevertheless,
it is normally a requirement for the maintainers of a distribution to
support all the packages necessary to build that distribution.
germinate therefore does not add all the packages that result from
following build-dependencies of seed packages and of their dependencies
(the “build-dependency tree”) to every output, unless they are also in
the seed or in the dependency list. Instead, it adds them to the output
for the last seed in the STRUCTURE file, conventionally called supported.
Like any other seed, the supported seed may contain its own list of
packages. It is common to provide support for many software packages
which are not in the default installation, such as debugging libraries,
optimised kernels, alternative language support, and the like.
Outputs
The output files are named after the seed to which they correspond. An
additional output file is needed for supported, namely
‘supported+build-depends’, which contains the supported list and the
build-depends lists of the other seeds all joined together. An ‘all’
output is produced to represent the entire archive.
Some other files are produced for occasional use by experts. See the
README file for full details on these.
OPTIONS
-v, --verbose
Be more verbose when processing seeds.
-S, --seed-source source,...
Fetch seeds from the specified sources. The default is
http://people.canonical.com/~ubuntu-archive/seeds/, or
http://bazaar.launchpad.net/~ubuntu-core-dev/ubuntu-seeds/ if the
--bzr option is used. You may use file:// URLs here to fetch seeds
from the local file system; for example, if your seeds are stored
in /home/username/seeds/debian.unstable, then you would use the
options -S file:///home/username/seeds/ -s debian.unstable.
-s, --seed-dist dist
Fetch seeds for distribution dist. The default is ubuntu.lucid.
-m, --mirror mirror
Get package lists from mirror. The default is
http://archive.ubuntu.com/ubuntu/. May be supplied multiple times;
the newest version of each package across all archives will win.
--source-mirror mirror
Get source package lists from mirror. The default is to use
package lists mirrors. May be supplied multiple times; the newest
version of each source package across all archives will win.
-d, --dist dist,...
Operate on the specified distributions. The default is lucid.
Listing multiple distributions may be useful, for example, when
examining both a released distribution and its security updates.
-a, --arch arch
Operate on architecture arch. The default is i386.
-c, --components component,...
Operate on the specified components. The default is main.
-i, --ipv6
Check IPv6 status of source packages, using the statistics
available at http://debdev.fabbione.net/stat/.
--bzr
Check out seeds from the bzr branch found at seed-source/seed-dist
rather than fetching them directly from a URL. Requires bzr to be
installed.
--no-rdepends
Disable reverse-dependency calculations. These calculations cause
a large number of small files to be written out in the rdepends/
directory, and may take some time.
--seed-packages parent/pkg,...
Treat each pkg as a seed by itself, inheriting from parent (i.e.
assuming that all packages in the parent seed are already installed
while calculating the additional dependencies of pkg). This allows
the use of germinate to calculate the dependencies of individual
extra packages. For example, --seed-packages
desktop/epiphany-browser will create an epiphany-browser output
file listing the additional packages that need to be installed over
and above the desktop seed in order to install epiphany-browser.
BUGS
The wiki-style markup in seeds was inherited from an early
implementation, and is a wart.
germinate can sometimes be confused by complicated situations involving
the order in which it encounters dependencies on virtual packages.
Explicit entries in seeds may be required to work around this.
Handling of installer packages (udebs) is complicated, poorly documented,
and doesn’t always work quite right: in particular, packages aren’t
demoted to the supported seed when they should be.
AUTHORS
Scott James Remnant 〈scott@canonical.com〉
Colin Watson 〈cjwatson@canonical.com〉
germinate is copyright © 2004, 2005, 2006, 2007, 2008 Canonical Ltd. See
the GNU General Public License version 2 or later for copying conditions.
A copy of the GNU General Public License is available in
/usr/share/common-licenses/GPL.