deb-control - Debian packages' master control file format
Each Debian package contains the master `control' file, which contains
a number of fields. Each field begins with a tag, such as Package or
Version (case insensitive), followed by a colon, and the body of the
field. Fields are delimited only by field tags. In other words, field
text may be multiple lines in length, but the installation tools will
generally join lines when processing the body of the field (except in
the case of the Description field, see below).
Package: <package name>
The value of this field determines the package name, and is used
to generate file names by most installation tools.
Version: <version string>
Typically, this is the original package's version number in
whatever form the program's author uses. It may also include a
Debian revision number (for non-native packages). If both version
and revision are supplied, they are seperated by a hyphen,
`-'. For this reason, the original version may not have a hyphen
in its version number.
Maintainer: <fullname email>
Should be in the format `Joe Bloggs <firstname.lastname@example.org>', and is
typically the person who created the package, as opposed to the
author of the software that was packaged.
Description: <short description>
The format for the package description is a short brief summary
on the first line (after the "Description" field). The following
lines can be used as a longer, more detailed description. Each
line of the long description must be preceded by a space, and
blank lines in the long desription must contain a single '.'
following the preceding space.
This is a general field that gives the package a category based
on the software that it installs. Some common sections are
`utils', `net', `mail', `text', `x11' etc.
Sets the importance of this package in relation to the system as
a whole. Common priorities are `required', `standard',
`optional', `extra' etc.
In Debian, the Section and Priority fields have a defined set of
accepted values based on the Policy Manual. They are used to decide
how the packages are layed out in the archive. A list of these can be
obtained from the latest version of debian-policy package.
This field is usually only needed when the answer is `yes'. It
denotes a package that is required for proper operation of the
system. Dpkg or any other installation tool will not allow an
Essential package to be removed (at least not without using one
of the force options).
The architecture specifies which type of hardware this package
was compiled for. Common architectures are `i386', `m68k',
`sparc', `alpha', `powerpc' etc. Note that the all option is
meant for packages that are architecture independent. Some examples
of this are shell or Perl scripts, or documentation.
Source: <source name>
The name of the source package that this binary package came
from, if different than the name of the package itself.
Depends: <package list>
List of packages that are required for this package to provide a
non-trivial amount of functionality. The package maintenance
software will not allow a package to be installed if the packages
listed in its Depends field aren't installed (at least not
without using the force options), and will run the postinst
scripts of packages listed in Depends: fields before those of
the packages which depend on them, and run prerm scripts before.
Pre-Depends: <package list>
List of packages that must be installed and configured before
this one can be installed. This is usually used in the case
where this package requires another package for running its preinst
Recommends: <package list>
Lists packages that would be found together with this one in all
but unusual installations. The package maintenance software
will warn the user if they install a package without those
listed in its Recommends field.
Suggests: <package list>
Lists packages that are related to this one and can perhaps
enhance its usefulness, but without which installing this package
is perfectly reasonable.
The syntax of Depends , Pre-Depends , Recommends and Suggests fields is
a list of groups of alternative packages. Each group is a list of
packages separated by vertical bar (or `pipe') symbols, `|'. The
groups are separated by commas. Commas are to be read as `AND', and
pipes as `OR', with pipes binding more tightly. Each item is a package
name optionally followed by a version number specification in parentheses.
A version number may start with a `>>', in which case any later version
will match, and may specify or omit the Debian packaging revision (separated
by a hyphen). Accepted version relationships are ">>" for
greater than, "<<" for less than, ">=" for greater than or equal to,
"<=" for less than or equal to, and "=" for equal to.
Conflicts: <package list>
Lists packages that conflict with this one, for example by containing
files with the same names. The package maintenance software
will not allow conflicting packages to be installed at the
same time. Two conflicting packages should each include a Con-
flicts line mentioning the other.
Replaces: <package list>
List of packages from which this package is allowed to replace
files. This is used for allowing this package to overwrite the
files of another package and is usually used with the Conflicts
field to force removal of the other package, if this one also
has the same files as the conflicted package.
Provides: <package list>
This is a list of virtual packages that this one provides.
Usuaully this is used in the case of several packages all providing
the same service. For example, sendmail and exim can can
serve as a mail server, so they provide a common package (`mailtransport-agent')
on which other packages can depend. This will
allow sendmail or exim to serve as a valid option to satisfy the
dependency. This prevents the packages that depend on a mail
server from having to know the package names for all of them,
and using `|' to separate the list.
The syntax of Conflicts , Replaces and Provides is a list of package
names, separated by commas (and optional whitespace). In the Conflicts
field, the comma should be read as `OR'. An optional version can also
be given with the same syntax as above for the Conflicts and Replaces
Maintainer: Wichert Akkerman <email@example.com>
Pre-Depends: libc6 (>= 2.0.105)
Description: GNU grep, egrep and fgrep.
The GNU family of grep utilities may be the "fastest grep in the west".
GNU grep is based on a fast lazy-state deterministic matcher (about
twice as fast as stock Unix egrep) hybridized with a Boyer-Moore-Gosper
search for a fixed string that eliminates impossible text from being
considered by the full regexp matcher without necessarily having to
look at every character. The result is typically many times faster
than Unix grep or egrep. (Regular expressions containing backreferencing
will run more slowly, however.)
deb(5), dpkg(8), dpkg-deb(1).
Debian Project January 2000 DEB-CONTROL(5)
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