deb-control - Debian packages' master control file format
Each Debian package contains the master `control' file, which contains a number
of fields, or comments when the line starts with '#'
. Each field begins
with a tag, such as Package
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). The exact format and sorting algorithm are
described in deb-version(5).
- 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 should
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
description must contain a single '.' following the preceding space.
- Section: section
- 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.
- Priority: priority
- Sets the importance of this package in relation to the system as a whole.
Common priorities are `required', `standard', `optional', `extra'
In Debian, the Section
fields have a defined set of
accepted values based on the Policy Manual. A list of these values can be
obtained from the latest version of the debian-policy
- Essential: yes|no
- 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
- Architecture: arch|all
- 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 and Perl
scripts, and documentation.
- Origin: name
- The name of the distribution this package is originating from.
- Bugs: url
- The url of the bug tracking system for this package. The current
used format is bts-type://bts-address, like
- Homepage: url
- The upstream project home page url.
- Tag: tag-list
- List of tags describing the qualities of the package. The description and
list of supported tags can be found in the debtags package.
- This field is used to indicate how this package should behave on a
multi-arch installations. The value same means that the package is
co-installable with itself, but it must not be used to satisfy the
dependency of any package of a different architecture from itself. The
value foreign means that the package is not co-installable with
itself, but should be allowed to satisfy the dependency of a package of a
different arch from itself. The value allowed allows
reverse-dependencies to indicate in their Depends field that they accept a
package from a foreign architecture, but has no effect otherwise. The
value no is the default when the field is omitted, in which case
adding the field with an explicit no value is generally not
- Source: source-name
- The name of the source package that this binary package came from, if
different than the name of the package itself.
- Subarchitecture: value
- Kernel-Version: value Installer-Menu-Item:
value These fields are used by the debian-installer and are usually
not needed. See /usr/share/doc/debian-installer/devel/modules.txt from the
debian-installer package for more details about them.
- 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). In an installation, the postinst scripts of packages
listed in Depends: fields are run before those of the packages which
depend on them. On the opposite, in a removal, the prerm script of a
package is run before those of the packages listed in its Depends:
- 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 script.
- 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
- 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
The syntax of Depends
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 package name is 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.
- Breaks: package-list
- Lists packages that this one breaks, for example by exposing bugs when the
named packages rely on this one. The package maintenance software will not
allow broken packages to be configured; generally the resolution is to
upgrade the packages named in a Breaks field.
- 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 Conflicts line mentioning the
- Replaces: package-list
- List of packages files from which this one replaces. 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
- Provides: package-list
- This is a list of virtual packages that this one provides. Usually this is
used in the case of several packages all providing the same service. For
example, sendmail and exim can serve as a mail server, so they provide a
common package (`mail-transport-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 Breaks
is a list of package names, separated by commas (and optional
whitespace). In the Breaks
fields, the comma
should be read as `OR'. An optional version can also be given with the same
syntax as above for the Breaks
- Built-Using: package-list
- This field lists extra source packages that were used during the build of
this binary package. This is an indication to the archive maintenance
software that these extra source packages must be kept whilst this binary
package is maintained. This field must be a list of source package names
with strict (=) version relationships. Note that the archive maintenance
software is likely to refuse to accept an upload which declares a
Built-Using relationship which cannot be satisfied within the
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).