debhelper(7)                        Debhelper                       debhelper(7)

       debhelper - the debhelper tool suite

       dh_* [-v] [-a] [-i] [--no-act] [-ppackage] [-Npackage] [-Ptmpdir]

       Debhelper is used to help you build a Debian package. The philosophy
       behind debhelper is to provide a collection of small, simple, and easily
       understood tools that are used in debian/rules to automate various common
       aspects of building a package. This means less work for you, the
       packager.  It also, to some degree means that these tools can be changed
       if Debian policy changes, and packages that use them will require only a
       rebuild to comply with the new policy.

       A typical debian/rules file that uses debhelper will call several
       debhelper commands in sequence, or use dh(1) to automate this process.
       Examples of rules files that use debhelper are in

       To create a new Debian package using debhelper, you can just copy one of
       the sample rules files and edit it by hand. Or you can try the dh-make
       package, which contains a dh_make command that partially automates the
       process. For a more gentle introduction, the maint-guide Debian package
       contains a tutorial about making your first package using debhelper.

       Except where the tool explicitly denotes otherwise, all of the debhelper
       tools assume that they run from the root directory of an unpacked source
       package.  This is so they can locate find files like debian/control when

       Here is the list of debhelper commands you can use. See their man pages
       for additional documentation.

           automatically builds a package

           automatically cleans up after a build

           automatically configure a package prior to building

           automatically runs make install or similar

           automatically runs a package's test suites

           install bug reporting customization files into package build

           build Debian binary packages

           clean up package build directories

           compress files and fix symlinks in package build directories

           optimize DWARF debug information in ELF binaries via dwz

           fix permissions of files in package build directories

           generate and install control file

           Update caches of Freedesktop icons

           install files into package build directories

           install declarative alternative rules

           install and register SGML Catalogs

           install changelogs into package build directories

           install cron scripts into etc/cron.*

           install files into the DEBIAN directory

           install files used by debconf in package build directories

           create subdirectories in package build directories

           install documentation into package build directories

           register an Emacs add on package

           install example files into package build directories

           install GSettings overrides and set dependencies

           install if-up and if-down hooks

           install info files

           install service init files into package build directories

           install initramfs hooks and setup maintscripts

           install logcheck rulefiles into etc/logcheck/

           install logrotate config files

           install man pages into package build directories

           install Debian menu files into package build directories

           install mime files into package build directories

           register kernel modules

           install pam support files

           install ppp ip-up and ip-down files

           install systemd unit files

           install systemd unit files

           install tmpfiles.d configuration files

           install udev rules files

           register a window manager

           register X fonts

           create symlinks in package build directories

           install lintian override files into package build directories

           list binary packages debhelper will act on

           automatically create shlibs file and call dpkg-gensymbols

           generate DEBIAN/md5sums file

           check for missing files

           move files out of debian/tmp into subpackages

           calculates Perl dependencies and cleans up after MakeMaker

           perform cleanups in preparation for building a binary package

           calculate shared library dependencies

           strip executables, shared libraries, and some static libraries

           enable/disable systemd unit files

           start/stop/restart systemd unit files

           test directory before building Debian package

           ensure that a package is built with necessary level of root

           register configuration files with ucf

           Update autotools config files

           migrate usr/local directories to maintainer scripts

   Deprecated Commands
       A few debhelper commands are deprecated and should not be used.

           install GConf defaults files and register schemas (deprecated)

           old-style man page installer (deprecated)

   Other Commands
       If a program's name starts with dh_, and the program is not on the above
       lists, then it is not part of the debhelper package, but it should still
       work like the other programs described on this page.

       Many debhelper commands make use of files in debian/ to control what they
       do. Besides the common debian/changelog and debian/control, which are in
       all packages, not just those using debhelper, some additional files can
       be used to configure the behavior of specific debhelper commands. These
       files are typically named debian/ (where package of course, is
       replaced with the package that is being acted on).

       For example, dh_installdocs uses files named debian/ to list
       the documentation files it will install. See the man pages of individual
       commands for details about the names and formats of the files they use.
       Generally, these files will list files to act on, one file per line. Some
       programs in debhelper use pairs of files and destinations or slightly
       more complicated formats.

       Note for the first (or only) binary package listed in debian/control,
       debhelper will use debian/foo when there's no debian/ file.
       However, it is often a good idea to keep the package. prefix as it is
       more explicit.  The primary exception to this are files that debhelper by
       default installs in every binary package when it does not have a package
       prefix (such as debian/copyright or debian/changelog).

       In some rare cases, you may want to have different versions of these
       files for different architectures or OSes. If files named
       debian/ or debian/ exist, where ARCH and OS
       are the same as the output of "dpkg-architecture -qDEB_HOST_ARCH" /
       "dpkg-architecture -qDEB_HOST_ARCH_OS", then they will be used in
       preference to other, more general files.

       Mostly, these config files are used to specify lists of various types of
       files. Documentation or example files to install, files to move, and so
       on.  When appropriate, in cases like these, you can use standard shell
       wildcard characters (? and * and [..] character classes) in the files.
       You can also put comments in these files; lines beginning with # are

       The syntax of these files is intentionally kept very simple to make them
       easy to read, understand, and modify.

   Substitutions in debhelper config files
       In compatibility level 13 and later, it is possible to use simple
       substitutions in debhelper config files for the following tools:

       •   dh_clean

       •   dh_install

       •   dh_installcatalogs

       •   dh_installdeb

       •   dh_installdirs

       •   dh_installdocs

       •   dh_installexamples

       •   dh_installinfo

       •   dh_installman

       •   dh_installwm

       •   dh_link

       •   dh_missing

       •   dh_ucf

       All substitution variables are of the form ${foo} and the braces are
       mandatory.  Variable names are case-sensitive and consist of
       alphanumerics (a-zA-Z0-9), hyphens (-), underscores (_), and colons (:).
       The first character must be an alphanumeric.

       If you need a literal dollar sign that cannot trigger a substitution, you
       can either use the ${Dollar} substitution or the sequence ${}.

       The following expansions are available:

           Expands to the relevant dpkg-architecture(1) value (similar to dpkg-
           architecture -qVARIABLE_HERE).

           When in doubt, the DEB_HOST_* variant is the one that will work both
           for native and cross builds.

           For performance reasons, debhelper will attempt to resolve these
           names from the environment first before consulting
           dpkg-architecture(1).  This is mostly mentioned for completeness as
           it will not matter for most cases.

           Expands to a single literal $-symbol.  This symbol will never be
           considered part of a substitution variable.  That is:

              # Triggers an error
              # Expands to the literal value "${NO_SUCH_TOKEN}"

           This variable equivalent to the sequence ${} and the two can be used

       Newline, Space, Tab
           Expands to a single ASCII newline, space and tab respectively.

           This can be useful if you need to include a literal whitespace
           character (e.g. space) where it would otherwise be stripped or used
           as a separator.

           Expands to the environment variable NAME.  The environment variable
           must be set (but can be set to the empty string).

       Note that all variables must expand to a defined value.  As an example,
       if debhelper sees ${env:FOO}, then it will insist that the environment
       variable FOO is set (it can be set to the empty string).

       Substitution limits

       To avoid infinite loops and resource exhaustion, debhelper will stop with
       an error if the text contains many substitution variables (50) or they
       expand beyond a certain size (4096 characters or 3x length of the
       original input - whichever is bigger).

   Executable debhelper config files
       If you need additional flexibility, many of the debhelper tools (e.g.
       dh_install(1)) support executing a config file as a script.

       To use this feature, simply mark the config file as executable (e.g.
       chmod +x debian/package.install) and the tool will attempt to execute it
       and use the output of the script.  In many cases, you can use dh-exec(1)
       as interpreter of the config file to retain most of the original syntax
       while getting the additional flexibility you need.

       When using executable debhelper config files, please be aware of the

       •   The executable config file must exit with success (i.e. its return
           code should indicate success).

       •   In compatibility level 13+, the output will be subject to
           substitutions (see "Substitutions in debhelper config files") where
           the tool support these.  Remember to be careful if your generator
           also provides substitutions as this can cause unnecessary confusion.

           Otherwise, the output will be used exactly as-is.  Notably, debhelper
           will not expand wildcards or strip comments or strip whitespace in
           the output.

       If you need the package to build on a file system where you cannot
       disable the executable bit, then you can use dh-exec(1) and its strip-
       output script.

       The following command line options are supported by all debhelper

       -v, --verbose
           Verbose mode: show all commands that modify the package build

           Do not really do anything. If used with -v, the result is that the
           command will output what it would have done.

       -a, --arch
           Act on architecture dependent packages that should be built for the
           DEB_HOST_ARCH architecture.

       -i, --indep
           Act on all architecture independent packages.

       -ppackage, --package=package
           Act on the package named package. This option may be specified
           multiple times to make debhelper operate on a given set of packages.

       -s, --same-arch
           Deprecated alias of -a.

           This option is removed in compat 12.

       -Npackage, --no-package=package
           Do not act on the specified package even if an -a, -i, or -p option
           lists the package as one that should be acted on.

           Do not act on the packages which have already been acted on by this
           debhelper command earlier (i.e. if the command is present in the
           package debhelper log).  For example, if you need to call the command
           with special options only for a couple of binary packages, pass this
           option to the last call of the command to process the rest of
           packages with default settings.

       -Ptmpdir, --tmpdir=tmpdir
           Use tmpdir for package build directory. The default is debian/package

           This little-used option changes the package which debhelper considers
           the "main package", that is, the first one listed in debian/control,
           and the one for which debian/foo files can be used instead of the
           usual debian/ files.

           This is used by dh(1) when passing user-specified options to all the
           commands it runs. If the command supports the specified option or
           option bundle, it will take effect. If the command does not support
           the option (or any part of an option bundle), it will be ignored.

       The following command line options are supported by some debhelper
       programs.  See the man page of each program for a complete explanation of
       what each option does.

       -n  Do not modify postinst, postrm, etc. scripts.

       -Xitem, --exclude=item
           Exclude an item from processing. This option may be used multiple
           times, to exclude more than one thing. The item is typically part of
           a filename, and any file containing the specified text will be

       -A, --all
           Makes files or other items that are specified on the command line
           take effect in ALL packages acted on, not just the first.

       The following command line options are supported by all of the dh_auto_*
       debhelper programs. These programs support a variety of build systems,
       and normally heuristically determine which to use, and how to use them.
       You can use these command line options to override the default behavior.
       Typically these are passed to dh(1), which then passes them to all the
       dh_auto_* programs.

       -Sbuildsystem, --buildsystem=buildsystem
           Force use of the specified buildsystem, instead of trying to auto-
           select one which might be applicable for the package.

           Pass none as buildsystem to disable auto-selection.

       -Ddirectory, --sourcedir=directory, --sourcedirectory=directory
           Assume that the original package source tree is at the specified
           directory rather than the top level directory of the Debian source
           package tree.

           Warning: The --sourcedir variant matches a similar named option in
           dh_install and dh_missing (etc.) for historical reasons.  While they
           have a similar name, they have very distinct purposes and in some
           cases it can cause errors when this variant is passed to dh (when
           then passes it on to all tools).

       -B[directory], --builddir[=directory], --builddirectory[=directory]
           Enable out of source building and use the specified directory as the
           build directory. If directory parameter is omitted, a default build
           directory will be chosen.

           If this option is not specified, building will be done in source by
           default unless the build system requires or prefers out of source
           tree building.  In such a case, the default build directory will be
           used even if --builddirectory is not specified.

           If the build system prefers out of source tree building but still
           allows in source building, the latter can be re-enabled by passing a
           build directory path that is the same as the source directory path.

       --parallel, --no-parallel
           Control whether parallel builds should be used if underlying build
           system supports them.  The number of parallel jobs is controlled by
           the DEB_BUILD_OPTIONS environment variable ("Debian Policy, section
           4.9.1") at build time. It might also be subject to a build system
           specific limit.

           If neither option is specified, debhelper currently defaults to
           --parallel in compat 10 (or later) and --no-parallel otherwise.

           As an optimization, dh will try to avoid passing these options to
           subprocesses, if they are unnecessary and the only options passed.
           Notably this happens when DEB_BUILD_OPTIONS does not have a parallel
           parameter (or its value is 1).

           This option implies --parallel and allows further limiting the number
           of jobs that can be used in a parallel build. If the package build is
           known to only work with certain levels of concurrency, you can set
           this to the maximum level that is known to work, or that you wish to

           Notably, setting the maximum to 1 is effectively the same as using

           By default, dh(1) will compute several environment (e.g. by using
           dpkg-buildflags(1)) and cache them to avoid having all dh_auto_* tool
           recompute them.

           When passing this option, the concrete dh_auto_* tool will ignore the
           cache from dh(1) and retrigger a rebuild of these variables.  This is
           useful in the very rare case where the package need to do multiple
           builds but with different ...FLAGS options.  A concrete example would
           be needing to change the -O parameter in CFLAGS in the second build:

               export DEB_CFLAGS_MAINT_APPEND=-O3

                   dh $@

                   dh_auto_configure -Bbuild-deb ...
                   DEB_CFLAGS_MAINT_APPEND=-Os dh_auto_configure \
                      --reload-all-buildenv-variables -Bbuild-udeb ...

           Without --reload-all-buildenv-variables in the second call to
           dh_auto_configure(1), the change in DEB_CFLAGS_MAINT_APPEND would be
           ignored as dh_auto_configure(1) would use the cached value of CFLAGS
           set by dh(1).

           This option is only available with debhelper (>= 12.7~) when the
           package uses compatibility level 9 or later.

       --list, -l
           List all build systems supported by debhelper on this system. The
           list includes both default and third party build systems (marked as
           such). Also shows which build system would be automatically selected,
           or which one is manually specified with the --buildsystem option.

       From time to time, major non-backwards-compatible changes need to be made
       to debhelper, to keep it clean and well-designed as needs change and its
       author gains more experience. To prevent such major changes from breaking
       existing packages, the concept of debhelper compatibility levels was
       introduced. You must tell debhelper which compatibility level it should
       use, and it modifies its behavior in various ways.

       In current debhelper, you can specify the compatibility level in
       debian/control by adding a Build-Depends on the debhelper-compat package.
       For example, to use v13 mode, ensure debian/control has:

         Build-Depends: debhelper-compat (= 13)

       This also serves as an appropriate versioned build dependency on a
       sufficient version of the debhelper package, so you do not need to
       specify a separate versioned build dependency on the debhelper package
       unless you need a specific point release of debhelper (such as for the
       introduction of a new feature or bugfix within a compatibility level).

       Note that debhelper does not provide debhelper-compat for experimental or
       beta compatibility levels; packages experimenting with those
       compatibility levels should use debian/compat or DH_COMPAT.

       Prior versions of debhelper required specifying the compatibility level
       in the file debian/compat, and current debhelper still supports this for
       backward compatibility, though a package may not specify a compatibility
       level via multiple methods at once. To use this method, debian/compat
       should contain the compatibility level as a single number, and no other
       content. If you specify the compatibility level by this method, your
       package will also need a versioned build dependency on a version of the
       debhelper package equal to (or greater than) the compatibility level your
       package uses. So, if you specify compatibility level 13 in debian/compat,
       ensure debian/control has:

         Build-Depends: debhelper (>= 13~)

       Unless otherwise indicated, all debhelper documentation assumes that you
       are using the most recent compatibility level, and in most cases does not
       indicate if the behavior is different in an earlier compatibility level,
       so if you are not using the most recent compatibility level, you're
       advised to read below for notes about what is different in earlier
       compatibility levels.

   Supported compatibility levels
       These are the available compatibility levels:

       v5  This is the lowest supported compatibility level.

           If you are upgrading from an earlier compatibility level, please
           review debhelper-obsolete-compat(7).

           This mode is deprecated.

       v6  Changes from v5 are:

           -       Commands that generate maintainer script fragments will order
                   the fragments in reverse order for the prerm and postrm

           -       dh_installwm will install a slave manpage link for
                   x-window-manager.1.gz, if it sees the man page in
                   usr/share/man/man1 in the package build directory.

           -       dh_builddeb did not previously delete everything matching
                   DH_ALWAYS_EXCLUDE, if it was set to a list of things to
                   exclude, such as CVS:.svn:.git. Now it does.

           -       dh_installman allows overwriting existing man pages in the
                   package build directory. In previous compatibility levels it
                   silently refuses to do this.

           This mode is deprecated.

       v7  Changes from v6 are:

           -       dh_install, will fall back to looking for files in debian/tmp
                   if it doesn't find them in the current directory (or wherever
                   you tell it look using --sourcedir). This allows dh_install
                   to interoperate with dh_auto_install, which installs to
                   debian/tmp, without needing any special parameters.

           -       dh_clean will read debian/clean and delete files listed

           -       dh_clean will delete toplevel *-stamp files.

           -       dh_installchangelogs will guess at what file is the upstream
                   changelog if none is specified.

           This mode is deprecated.

       v8  Changes from v7 are:

           -       Commands will fail rather than warning when they are passed
                   unknown options.

           -       dh_makeshlibs will run dpkg-gensymbols on all shared
                   libraries that it generates shlibs files for. So -X can be
                   used to exclude libraries.  Also, libraries in unusual
                   locations that dpkg-gensymbols would not have processed
                   before will be passed to it, a behavior change that can cause
                   some packages to fail to build.

           -       dh requires the sequence to run be specified as the first
                   parameter, and any switches come after it. Ie, use "dh $@
                   --foo", not "dh --foo $@".

           -       dh_auto_* prefer to use Perl's Module::Build in preference to

           This mode is deprecated.

       v9  Changes from v8 are:

           -       Multiarch support. In particular, dh_auto_configure passes
                   multiarch directories to autoconf in --libdir and

           -       dh is aware of the usual dependencies between targets in
                   debian/rules.  So, "dh binary" will run any build, build-
                   arch, build-indep, install, etc targets that exist in the
                   rules file. There's no need to define an explicit binary
                   target with explicit dependencies on the other targets.

           -       dh_strip compresses debugging symbol files to reduce the
                   installed size of -dbg packages.

           -       dh_auto_configure does not include the source package name in
                   --libexecdir when using autoconf.

           -       dh does not default to enabling --with=python-support

                   (Obsolete: As the dh_pysupport tool was removed from Debian
                   stretch.  Since debhelper/10.3, dh no longer enables this
                   sequence add-on regardless of compat level)

           -       All of the dh_auto_* debhelper programs and dh set
                   environment variables listed by dpkg-buildflags, unless they
                   are already set.

           -       dh_auto_configure passes dpkg-buildflags CFLAGS, CPPFLAGS,
                   and LDFLAGS to perl Makefile.PL and Build.PL

           -       dh_strip puts separated debug symbols in a location based on
                   their build-id.

           -       Executable debhelper config files are run and their output
                   used as the configuration.

           This mode is deprecated.

       v10 Changes from v9 are:

           -       dh_installinit will no longer install a file named
                   debian/package as an init script.

           -       dh_installdocs will error out if it detects links created
                   with --link-doc between packages of architecture "all" and
                   non-"all" as it breaks binNMUs.

           -       dh_installdeb no longer installs a maintainer-provided
                   debian/package.shlibs file.  This is now done by
                   dh_makeshlibs instead.

           -       dh_installwm refuses to create a broken package if no man
                   page can be found (required to register for the x-window-
                   manager alternative).

           -       Debhelper will default to --parallel for all buildsystems
                   that support parallel building.  This can be disabled by
                   using either --no-parallel or passing --max-parallel with a
                   value of 1.

           -       The dh command will not accept any of the deprecated "manual
                   sequence control" parameters (--before, --after, etc.).
                   Please use override targets instead.

                   Retroactively applied to earlier compat levels: dh no longer
                   accepts any of these since debhelper/12.4.

           -       The dh command will no longer use log files to track which
                   commands have been run.  The dh command still keeps track of
                   whether it already ran the "build" sequence and skip it if it

                   The main effects of this are:

                   -   With this, it is now easier to debug the install or/and
                       binary sequences because they can now trivially be re-run
                       (without having to do a full "clean and rebuild" cycle)

                   -   The main caveat is that dh_* now only keeps track of what
                       happened in a single override target.  When all the calls
                       to a given dh_cmd command happens in the same override
                       target everything will work as before.

                       Example of where it can go wrong:

                           dh_foo -pmy-pkg

                           dh_foo --remaining

                       In this case, the call to dh_foo --remaining will also
                       include my-pkg, since dh_foo -pmy-pkg was run in a
                       separate override target.  This issue is not limited to
                       --remaining, but also includes -a, -i, etc.

           -       The dh_installdeb command now shell-escapes the lines in the
                   maintscript config file.  This was the original intent but it
                   did not work properly and packages have begun to rely on the
                   incomplete shell escaping (e.g. quoting file names).

           -       The dh_installinit command now defaults to
                   --restart-after-upgrade.  For packages needing the previous
                   behaviour, please use --no-restart-after-upgrade.

           -       The autoreconf sequence is now enabled by default.  Please
                   pass --without autoreconf to dh if this is not desirable for
                   a given package

           -       The systemd sequence is now enabled by default.  Please pass
                   --without systemd to dh if this is not desirable for a given

           -       Retroactively removed: dh no longer creates the package build
                   directory when skipping running debhelper commands. This will
                   not affect packages that only build with debhelper commands,
                   but it may expose bugs in commands not included in debhelper.

                   This compatibility feature had a bug since its inception in
                   debhelper/9.20130516 that made it fail to apply in compat 9
                   and earlier.  As there has been no reports of issues caused
                   by this bug in those ~5 years, this item have been removed
                   rather than fixed.

       v11 This mode is discouraged.

           The compat 11 is discouraged for new packages as it suffers from
           feature interaction between dh_installinit and dh_installsystemd
           causing services to not run correctly in some cases.  Please consider
           using compatibility mode 10 or 12 instead.  More details about the
           issue are available in Debian#887904 and

           Changes from v10 are:

           -       dh_installinit no longer installs service or tmpfile files,
                   nor generates maintainer scripts for those files.  Please use
                   the new dh_installsystemd helper.

           -       The dh_systemd_enable and dh_systemd_start helpers have been
                   replaced by the new dh_installsystemd helper.  For the same
                   reason, the systemd sequence for dh has also been removed.
                   If you need to disable the dh_installsystemd helper tool,
                   please use an empty override target.

                   Please note that the dh_installsystemd tool has a slightly
                   different behaviour in some cases (e.g. when using the --name

           -       dh_installdirs no longer creates debian/package directories
                   unless explicitly requested (or it has to create a
                   subdirectory in it).

                   The vast majority of all packages will be unaffected by this

           -       The makefile buildsystem now passes INSTALL="install
                   --strip-program=true" to make(1).  Derivative buildsystems
                   (e.g. configure or cmake) are unaffected by this change.

           -       The autoconf buildsystem now passes --runstatedir=/run to

           -       The cmake buildsystem now passes
                   -DCMAKE_INSTALL_RUNSTATEDIR=/run to cmake(1).

           -       dh_installman will now prefer detecting the language from the
                   path name rather than the extension.

           -       dh_auto_install will now only create the destination
                   directory it needs.  Previously, it would create the package
                   build directory for all packages.  This will not affect
                   packages that only build with debhelper commands, but it may
                   expose bugs in commands not included in debhelper.

           -       The helpers dh_installdocs, dh_installexamples,
                   dh_installinfo, and dh_installman now error out if their
                   config has a pattern that does not match anything or
                   reference a path that does not exist.

                   Known exceptions include building with the nodoc profile,
                   where the above tools will silently permit failed matches
                   where the patterns are used to specify documentation.

           -       The helpers dh_installdocs, dh_installexamples,
                   dh_installinfo, and dh_installman now accept the parameter
                   --sourcedir with same meaning as dh_install. Furthermore,
                   they now also fall back to debian/tmp like dh_install.

                   Migration note: A bug in debhelper 11 up to 11.1.5 made
                   dh_installinfo incorrectly ignore --sourcedir.

           -       The perl-makemaker and perl-build build systems no longer
                   pass -I. to perl.  Packages that still need this behaviour
                   can emulate it by using the PERL5LIB environment variable.
                   E.g. by adding export PERL5LIB=. in their debian/rules file
                   (or similar).

           -       The PERL_USE_UNSAFE_INC environment variable is no longer set
                   by dh or any of the dh_auto_* tools.  It was added as a
                   temporary work around to avoid a lot of packages failing to
                   build at the same time.

                   Note this item will eventually become obsolete as upstream
                   intends to drop support for the PERL_USE_UNSAFE_INC
                   environment variable.  When perl drops support for it, then
                   this variable will be removed retroactively from existing
                   compat levels as well.

           -       The dh_makeshlibs helper will now exit with an error if
                   objdump returns a non-zero exit from analysing a given file.

           -       The dh_installdocs and dh_installexamples tools may now
                   install most of the documentation in a different path to
                   comply with the recommendation from Debian policy §12.3
                   (since version 3.9.7).

                   Note that if a given source package only contains a single
                   binary package in debian/control or none of the packages are
                   -doc packages, then this change is not relevant for that
                   source package and you can skip to the next change.

                   By default, these tools will now attempt to determine a "main
                   package for the documentation" (called a doc-main-package
                   from here on) for every -doc package.  If they find such a
                   doc-main-package, they will now install the documentation
                   into the path /usr/share/doc/doc-main-package in the given
                   doc package.  I.e. the path can change but the documentation
                   is still shipped in the -doc package.

                   The --doc-main-package option can be used when the auto-
                   detection is insufficient or to reset the path to its
                   previous value if there is a reason to diverge from Debian
                   policy recommendation.

                   Some documentation will not be affected by this change.
                   These exceptions include the copyright file, changelog files,
                   README.Debian, etc.  These files will still be installed in
                   the path /usr/share/doc/package.

           -       The dh_strip and dh_shlibdeps tools no longer uses filename
                   patterns to determine which files to process.  Instead, they
                   open the file and look for an ELF header to determine if a
                   given file is an shared object or an ELF executable.

                   This change may cause the tools to process more files than

       v12 Changes from v11 are:

           -       The dh_makeshlibs tool now generates shlibs files with
                   versioned dependency by default.  This means that
                   -VUpstream-Version (a.k.a. -V) is now the default.

                   If an unversioned dependency in the shlibs file is wanted,
                   this can be obtained by passing -VNone instead.  However,
                   please see dh_makeshlibs(1) for the caveat of unversioned

           -       The -s (--same-arch) option is removed.  Please use -a
                   (--arch) instead.

           -       Invoking dh_clean -k now causes an error instead of a
                   deprecation warning.

           -       The --no-restart-on-upgrade option in dh_installinit has been
                   removed.  Please use the new name --no-stop-on-upgrade

           -       There was a bug in the doit (and similar) functions from
                   Debian::Debhelper::Dh_Lib that made them spawn a shell in one
                   particular circumstance.  This bug is now removed and will
                   cause helpers that rely on the bug to fail with a "command
                   not found"-error.

           -       The --list-missing and --fail-missing in dh_install has been
                   removed.  Please use dh_missing and its corresponding
                   options, which can also see the files installed by other

           -       The dh_installinit helper no longer installs configuration
                   for the upstart init system.  Instead, it will abort the
                   build if it finds an old upstart configuration file.  The
                   error is there to remind the package maintainer to ensure the
                   proper removal of the conffiles shipped in previous versions
                   of the package (if any).

           -       The dh_installdeb tool will do basic validation of some
                   dpkg-maintscript-helper(1) commands and will error out if the
                   commands appear to be invalid.

           -       The dh_missing tool will now default to --list-missing.

           -       The dh_makeshlibs tool will now only pass libraries to
                   dpkg-gensymbols(1) if the ELF binary has a SONAME (containing

           -       The dh_compress tool no longer compresses examples (i.e.
                   anything installed in </usr/share/doc/package/examples>.)

           -       The standard sequence in dh now includes dh_dwz and
                   dh_installinitramfs by default.  This makes the dwz and
                   installinitramfs sequences obsolete and they will now fail
                   with an error.  If you want to skip these commands, then
                   please insert an empty override target for them in
                   debian/rules (e.g. override_dh_dwz:)

           -       The build systems meson and autoconf no longer explicitly set
                   the --libexecdir variable and thus relies on the build system
                   default - which should be /usr/libexec (per FHS 3.0, adopted
                   in Debian Policy 4.1.5).

                   If a particular upstream package does not use the correct
                   default, the parameter can often be passed manually via
                   dh_auto_configure(1).  E.g.  via the following example:

                           dh_auto_configure -- --libexecdir=/usr/libexec

                   Note the -- before the --libexecdir parameter.

           -       The dh_installdeb tool no longer installs the maintainer
                   provided conffiles file.  The file has mostly been obsolete
                   since compatibility level 3, where dh_installdeb began to
                   automatically compute the resulting conffiles control file.

           -       The dh_installsystemd tool no longer relies on dh_installinit
                   for handling systemd services that have a sysvinit
                   alternative.  Both tools must now be used in such a case to
                   ensure the service is properly started under both sysvinit
                   and systemd.

                   If you have an override for dh_installinit (e.g. to call it
                   with --no-start) then you will probably need one for
                   dh_installsystemd as well now.

                   This change makes dh_installinit inject a misc:Pre-Depends
                   for init-system-helpers (>= 1.54~).  Please ensure that the
                   package lists ${misc:Pre-Depends} in its Pre-Depends field
                   before upgrading to compat 12.

           -       The third-party dh_golang tool (from dh-golang package) now
                   defaults on honoring DH_GOLANG_EXCLUDES variable for source
                   installation in -dev packages and not only during the
                   building process. Please set DH_GOLANG_EXCLUDES_ALL to false
                   to revert to the previous behaviour. See
                   Debian::Debhelper::Buildsystem::golang(3pm) for details and

           -       dh_installsystemduser is now included in the dh standard
                   sequence by default.

           -       The python-distutils buildsystem is now removed.  Please use
                   the third-party build system pybuild instead.

       v13 This is the recommended mode of operation.

           Changes from v12 are:

           -       The meson+ninja build system now uses meson test instead of
                   ninja test when running the test suite.  Any override of
                   dh_auto_test that passes extra parameters to upstream test
                   runner should be reviewed as meson test is not command line
                   compatible with ninja test.

           -       All debhelper like tools based on the official debhelper
                   library (including dh and the official dh_* tools) no longer
                   accepts abbreviated command parameters.  At the same time, dh
                   now optimizes out calls to redundant dh_* helpers even when
                   passed long command line options.

           -       The ELF related debhelper tools (dh_dwz, dh_strip,
                   dh_makeshlibs, dh_shlibdeps) are now only run for arch
                   dependent packages by default (i.e. they are excluded from
                   *-indep targets and are passed -a by default). If you need
                   them for *-indep targets, you can add an explicit Build-
                   Depends on dh-sequence-elf-tools.

           -       The third-party gradle build system (from gradle-debian-
                   helper package) now runs the upstream-provided test suite
                   automatically.  To suppress such behavior, override

           -       The dh_installman tool now aborts if it sees conflicting
                   definitions of a manpage.  This typically happens if the
                   upstream build system is installing a compressed version and
                   the package lists an uncompressed version of the manpage in
                   debian/package.manpages.  Often the easiest fix is to remove
                   the manpage from debian/package.manpages (assuming both
                   versions are identical).

           -       The dh_auto_* helpers now resets the environment variables
                   HOME and common XDG_* variable.  Please see description of
                   the environment variables in "ENVIRONMENT" for how this

                   This feature changed between between debhelper 13 and
                   debhelper 13.2.

           -       The dh command will now error if an override or hook target
                   for an obsolete command are present in debian/rules (e.g.

           -       The dh_missing command will now default to --fail-missing.
                   This can be reverted to a non-fatal warning by explicitly
                   passing --list-missing like it was in compat 12.

                   If you do not want the warning either, please omit the call
                   to dh_missing.  If you use the dh command sequencer, then you
                   can do this by inserting an empty override target in the
                   debian/rules file of the relevant package.  As an example:

                       # Disable dh_missing

           -       The dh command sequencer now runs dh_installtmpfiles in the
                   default sequence.  The dh_installtmpfiles takes over handling
                   of tmpfiles.d configuration files.  Related functionality in
                   dh_installsystemd is now disabled.

                   Note that dh_installtmpfiles responds to
                   debian/package.tmpfiles where dh_installsystemd used a name
                   without the trailing "s".

           -       Many dh_* tools now support limited variable expansion via
                   the ${foo} syntax.  In many cases, this can be used to
                   reference paths that contain either spaces or
                   dpkg-architecture(1) values.  While this can reduce the need
                   for dh-exec(1) in some cases, it is not a replacement
                   dh-exec(1) in general.  If you need filtering, renaming,
                   etc., the package will still need dh-exec(1).

                   Please see "Substitutions in debhelper config files" for
                   syntax and available substitution variables.  To dh_* tool
                   writers, substitution expansion occurs as a part of the
                   filearray and filedoublearray functions.

           -       The dh command sequencer will now skip all hook and override
                   targets for dh_auto_test, dh_dwz and dh_strip when
                   DEB_BUILD_OPTIONS lists the relevant nocheck / nostrip

                   Any package relying on these targets to always be run should
                   instead move relevant logic out of those targets.  E.g. non-
                   test related packaging code from override_dh_auto_test would
                   have to be moved to execute_after_dh_auto_build or

           -       The cmake buildsystem now passes
                   -DCMAKE_SKIP_INSTALL_ALL_DEPENDENCY=ON to cmake(1) to speed
                   up automatic installation process. If for some reason you
                   need previous behavior, override the flag:

                       dh_auto_configure -- -DCMAKE_SKIP_INSTALL_ALL_DEPENDENCY=OFF ...

       v14 This compatibility level is still open for development; use with

           Changes from v13 are:

           -       The cmake buildsystem now passes -DCMAKE_SKIP_RPATH=ON and
                   -DBUILD_RPATH_USE_ORIGIN=ON to cmake(1) to avoid some
                   reproducibility issues.

                   This can cause issues with running binaries directly from the
                   build directories as they might now require a manually set
                   LD_LIBRARY_PATH.  If you need to override this change, we
                   recommend that you try to pass the -DCMAKE_SKIP_RPATH=OFF
                   option first to see if that fixes the problem (leaving
                   BUILD_RPATH_USE_ORIGIN at its new default).  This should undo
                   the need for LD_LIBRARY_PATH and avoid the reproducibility
                   issues on Linux, where $ORIGIN is supported by the runtime

   Multiple binary package support
       If your source package generates more than one binary package, debhelper
       programs will default to acting on all binary packages when run. If your
       source package happens to generate one architecture dependent package,
       and another architecture independent package, this is not the correct
       behavior, because you need to generate the architecture dependent
       packages in the binary-arch debian/rules target, and the architecture
       independent packages in the binary-indep debian/rules target.

       To facilitate this, as well as give you more control over which packages
       are acted on by debhelper programs, all debhelper programs accept the -a,
       -i, -p, and -s parameters. These parameters are cumulative.  If none are
       given, debhelper programs default to acting on all packages listed in the
       control file, with the exceptions below.

       First, any package whose Architecture field in debian/control does not
       match the DEB_HOST_ARCH architecture will be excluded ("Debian Policy,
       section 5.6.8").

       Also, some additional packages may be excluded based on the contents of
       the DEB_BUILD_PROFILES environment variable and Build-Profiles fields in
       binary package stanzas in debian/control, according to the draft policy
       at <>.

       Interaction between package selections and Build-Profiles

       Build-Profiles affect which packages are included in the package
       selections mechanisms in debhelper.  Generally, the package selections
       are described from the assumption that all packages are enabled.  This
       section describes how the selections react when a package is disabled due
       to the active Build-Profiles (or lack of active Build-Profiles).

       -a/--arch, -i/--indep OR no selection options (a raw "dh_X" call)
           The package disabled by Build-Profiles is silently excluded from the

           Note you will receive a warning if all packages related to these
           selections are disabled.  In that case, it generally does not make
           sense to do the build in the first place.

       -N package / --no-package package
           The option is accepted and effectively does nothing.

       -p package / --package package
           The option is accepted, but debhelper will not act on the package.

       Note that it does not matter whether a package is enabled or disabled by

   Automatic generation of Debian install scripts
       Some debhelper commands will automatically generate parts of Debian
       maintainer scripts. If you want these automatically generated things
       included in your existing Debian maintainer scripts, then you need to add
       #DEBHELPER# to your scripts, in the place the code should be added.
       #DEBHELPER# will be replaced by any auto-generated code when you run

       If a script does not exist at all and debhelper needs to add something to
       it, then debhelper will create the complete script.

       All debhelper commands that automatically generate code in this way let
       it be disabled by the -n parameter (see above).

       Note that the inserted code will be shell code, so you cannot directly
       use it in a Perl script. If you would like to embed it into a Perl
       script, here is one way to do that (note that I made sure that $1, $2,
       etc are set with the set command):

         my $temp="set -e\nset -- @ARGV\n" . << 'EOF';
         if (system($temp)) {
            my $exit_code = ($? >> 8) & 0xff;
            my $signal = $? & 0x7f;
            if ($exit_code) {
                die("The debhelper script failed with error code: ${exit_code}");
            } else {
                die("The debhelper script was killed by signal: ${signal}");

   Automatic generation of miscellaneous dependencies.
       Some debhelper commands may make the generated package need to depend on
       some other packages. For example, if you use dh_installdebconf(1), your
       package will generally need to depend on debconf. Or if you use
       dh_installxfonts(1), your package will generally need to depend on a
       particular version of xutils. Keeping track of these miscellaneous
       dependencies can be annoying since they are dependent on how debhelper
       does things, so debhelper offers a way to automate it.

       All commands of this type, besides documenting what dependencies may be
       needed on their man pages, will automatically generate a substvar called
       ${misc:Depends}. If you put that token into your debian/control file, it
       will be expanded to the dependencies debhelper figures you need.

       This is entirely independent of the standard ${shlibs:Depends} generated
       by dh_makeshlibs(1), and the ${perl:Depends} generated by dh_perl(1).
       You can choose not to use any of these, if debhelper's guesses don't
       match reality.

   Package build directories
       By default, all debhelper programs assume that the temporary directory
       used for assembling the tree of files in a package is debian/package.

       Sometimes, you might want to use some other temporary directory. This is
       supported by the -P flag. For example, "dh_installdocs -Pdebian/tmp",
       will use debian/tmp as the temporary directory. Note that if you use -P,
       the debhelper programs can only be acting on a single package at a time.
       So if you have a package that builds many binary packages, you will need
       to also use the -p flag to specify which binary package the debhelper
       program will act on.

       Debhelper includes support for udebs. To create a udeb with debhelper,
       add "Package-Type: udeb" to the package's stanza in debian/control.
       Debhelper will try to create udebs that comply with debian-installer
       policy, by making the generated package files end in .udeb, not
       installing any documentation into a udeb, skipping over preinst, postrm,
       prerm, and config scripts, etc.

       This section describes some of the environment variables that influences
       the behaviour of debhelper or which debhelper interacts with.

       It is important to note that these must be actual environment variables
       in order to affect the behaviour of debhelper (not simply Makefile
       variables).  To specify them properly in debian/rules, be sure to
       "export" them. For example, "export DH_VERBOSE".

           Set to 1 to enable verbose mode. Debhelper will output every command
           it runs. Also enables verbose build logs for some build systems like

           Set to 1 to enable quiet mode. Debhelper will not output commands
           calling the upstream build system nor will dh print which subcommands
           are called and depending on the upstream build system might make that
           more quiet, too.  This makes it easier to spot important messages but
           makes the output quite useless as buildd log.  Ignored if DH_VERBOSE
           is also set.

           Temporarily specifies what compatibility level debhelper should run
           at, overriding any value specified via Build-Depends on debhelper-
           compat or via the debian/compat file.

           Set to 1 to enable no-act mode.

           All debhelper tools will parse command line arguments listed in this
           variable before any command option (as if they had been prepended to
           the command line arguments).  Unfortunately, some third-party
           provided tools may not support this variable and will ignore these
           command line arguments.

           When using dh(1), it can be passed options that will be passed on to
           each debhelper command, which is generally better than using

           If set, this adds the value the variable is set to to the -X options
           of all commands that support the -X option. Moreover, dh_builddeb
           will rm -rf anything that matches the value in your package build

           This can be useful if you are doing a build from a CVS source tree,
           in which case setting DH_ALWAYS_EXCLUDE=CVS will prevent any CVS
           directories from sneaking into the package you build. Or, if a
           package has a source tarball that (unwisely) includes CVS
           directories, you might want to export DH_ALWAYS_EXCLUDE=CVS in
           debian/rules, to make it take effect wherever your package is built.

           Multiple things to exclude can be separated with colons, as in

           If set, this adds the specified dh addons to be run in the
           appropriate places in the sequence of commands. This is equivalent to
           specifying the addon to run with the --with flag in the debian/rules
           file. Any --without calls specifying an addon in this environment
           variable will not be run.

           This is intended to be used by downstreams or specific local
           configurations that require a debhelper addon to be run during
           multiple builds without having to patch a large number of rules file.
           If at all possible, this should be avoided in favor of a --with flag
           in the rules file.

           These variables can be used to control whether debhelper commands
           should use colors in their textual output.  Can be set to "always",
           "auto" (the default), or "never".

           Note that DPKG_COLOR also affects a number of dpkg related tools and
           debhelper uses it on the assumption that you want the same color
           setting for dpkg and debhelper.  In the off-hand chance you want
           different color setting for debhelper, you can use DH_COLORS instead
           or in addition to DPKG_COLORS.

           If no explicit request for color has been given (e.g. DH_COLORS and
           DPKG_COLORS are both unset), the presence of this environment
           variable cause the default color setting to be "never".

           The variable is defined according to <>.  In
           this project, the environment variables (such as DH_COLORS) are
           considered an explicit request for color.

           By default (in any non-deprecated compat level), debhelper will
           automatically set these flags by using dpkg-buildflags(1), when they
           are unset.  If you need to change the default flags, please use the
           features from dpkg-buildflags(1) to do this (e.g.
           DEB_BUILD_MAINT_OPTIONS=hardening=all or
           DEB_CPPFLAGS_MAINT_APPEND=-DCUSTOM_MACRO=true) rather than setting
           the concrete variable directly.

       HOME, XDG_*
           In compat 13 and later, these environment variables are reset before
           invoking the upstream build system via the dh_auto_* helpers.  The
           variables HOME (all dh_auto_* helpers)and XDG_RUNTIME_DIR
           (dh_auto_test only) will be set to a writable directory. All
           remaining variables and XDG_RUNTIME_DIR (except for during
           dh_auto_test) will be cleared.

           The HOME directory will be created as an empty directory but it will
           be reused between calls to dh_auto_*.  Any content will persist until
           explicitly deleted or dh_clean.

           Please see "Supported flags in DEB_BUILD_OPTIONS" for this
           environment variable.

           Please note that this variable should not be altered by package
           maintainers inside debian/rules to change the behaviour of debhelper.
           Instead, where the package maintainer need these features, they
           should look disabling the relevant feature directly (e.g. by
           overriding the concrete tools).

           This is a dpkg specific environment variable (see e.g.
           dpkg-buildflags(1)).  The debhelper tool suite silently ignores it.

           It is documented here because it has a similar name to
           DEB_BUILD_OPTIONS, which make some people mistakenly assume that
           debhelper will also react to this variable.

   Supported flags in DEB_BUILD_OPTIONS
       The debhelper tool suite reacts to the following flags in

           This is a debhelper specific value.

           When dherroron is present and set to obsolete-compat-levels, then
           debhelper tools will promote deprecation warnings for usage of old
           soon to be removed compat levels into errors.

           This is useful for automated checking for code relying on deprecated
           compat levels that is scheduled for removal.

           This option is intended for testing purposes; not production builds.

           This value will change the content of the debs being built.  The .deb
           packages built when this is set is therefore not bit-for-bit
           reproducible with a regular build in the general case.

           This value will cause the official debhelper tools will skip actions
           and helpers that either remove, detach or deduplicate debugging
           symbols in ELF binaries.

           This value affects dh_dwz(1) and dh_strip(1).

           This value will cause the official debhelper build systems to skip
           runs of upstream test suites.

           Package maintainers looking to avoid running the upstream tests
           should not rely on this.  Instead, they can add an empty override
           target to skip dh_auto_test.

           This value affects dh_auto_test(1).

           This value will change the content of the debs being built.  The .deb
           packages built when this is set is therefore not bit-for-bit
           reproducible with a regular build in the general case.

           This value will cause several debhelper tools to skip installation of
           documentation such as manpages or upstream provided documentation.
           Additionally, the tools will also ignore if declared documentation is
           "missing" on the assumption that the documentation has not been

           This value effects tools like dh_installdocs(1), which knows it is
           working with documentation.

       noautodbgsym, noddebs
           The official name is autodbgsym.  The noddebs variant is accepted for
           historical reasons.

           This value causes debhelper to skip the generation of automatically
           generated debug symbol packages.

           This value affects dh_strip(1).

           This value enables debhelper to use up to N threads or processes
           (subject to parameters like --no-parallel and --max-parallel=M).  Not
           all debhelper tools work with parallel tasks and may silently ignore
           the request.

           This value affects many debhelper tools.  Most notably dh_auto_*,
           which will attempt to run the underlying upstream build system with
           that number of threads.

           This value will cause the official debhelper build systems to
           configure upstream builds to be terse (i.e. reduce verbosity in their
           output).  This is subject to the upstream and the debhelper build
           system supporting such features.

           This value affects most dh_auto_* tools.

       Unknown flags are silently ignored.

       Note third-party debhelper-like tools or third-party provided build
       systems may or may not react to the above flags.  This tends to depend on
       implementation details of the tool.

           A set of example debian/rules files that use debhelper.

           Debhelper web site.

       Joey Hess <>

13.2.1ubuntu1                      2020-09-13                       debhelper(7)