NAME¶

debhelper - the debhelper tool suite

SYNOPSIS¶

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

DESCRIPTION¶

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 /usr/share/doc/debhelper/examples/

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 needed.

DEBHELPER COMMANDS¶

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

dh_assistant(1)

tool for supporting debhelper tools and provide introspection

dh_auto_build(1)

automatically builds a package

dh_auto_clean(1)

automatically cleans up after a build

dh_auto_configure(1)

automatically configure a package prior to building

dh_auto_install(1)

automatically runs make install or similar

dh_auto_test(1)

automatically runs a package's test suites

dh_bugfiles(1)

install bug reporting customization files into package build directories

dh_builddeb(1)

build Debian binary packages

dh_clean(1)

clean up package build directories

dh_compress(1)

compress files and fix symlinks in package build directories

dh_dwz(1)

optimize DWARF debug information in ELF binaries via dwz

dh_fixperms(1)

fix permissions of files in package build directories

dh_gencontrol(1)

generate and install control file

dh_icons(1)

Update caches of Freedesktop icons

dh_install(1)

install files into package build directories

dh_installalternatives(1)

install declarative alternative rules

dh_installcatalogs(1)

install and register SGML Catalogs

dh_installchangelogs(1)

install changelogs into package build directories

dh_installcron(1)

install cron scripts into etc/cron.*

dh_installdeb(1)

install files into the DEBIAN directory

dh_installdebconf(1)

install files used by debconf in package build directories

dh_installdirs(1)

create subdirectories in package build directories

dh_installdocs(1)

install documentation into package build directories

dh_installemacsen(1)

register an Emacs add on package

dh_installexamples(1)

install example files into package build directories

dh_installgsettings(1)

install GSettings overrides and set dependencies

dh_installifupdown(1)

install if-up and if-down hooks

dh_installinfo(1)

install info files

dh_installinit(1)

install service init files into package build directories

dh_installinitramfs(1)

install initramfs hooks and setup maintscripts

dh_installlogcheck(1)

install logcheck rulefiles into etc/logcheck/

dh_installlogrotate(1)

install logrotate config files

dh_installman(1)

install man pages into package build directories

dh_installmenu(1)

install Debian menu files into package build directories

dh_installmime(1)

install mime files into package build directories

dh_installmodules(1)

register kernel modules

dh_installpam(1)

install pam support files

dh_installppp(1)

install ppp ip-up and ip-down files

dh_installsystemd(1)

install systemd unit files

dh_installsystemduser(1)

install systemd unit files

dh_installsysusers(1)

install and integrates systemd sysusers files

dh_installtmpfiles(1)

install tmpfiles.d configuration files

dh_installudev(1)

install udev rules files

dh_installwm(1)

register a window manager

dh_installxfonts(1)

register X fonts

dh_link(1)

create symlinks in package build directories

dh_lintian(1)

install lintian override files into package build directories

dh_listpackages(1)

list binary packages debhelper will act on

dh_makeshlibs(1)

automatically create shlibs file and call dpkg-gensymbols

dh_md5sums(1)

generate DEBIAN/md5sums file

dh_missing(1)

check for missing files

dh_movefiles(1)

move files out of debian/tmp into subpackages

dh_perl(1)

calculates Perl dependencies and cleans up after MakeMaker

dh_prep(1)

perform cleanups in preparation for building a binary package

dh_shlibdeps(1)

calculate shared library dependencies

dh_strip(1)

strip executables, shared libraries, and some static libraries

dh_systemd_enable(1)

enable/disable systemd unit files

dh_systemd_start(1)

start/stop/restart systemd unit files

dh_testdir(1)

test directory before building Debian package

dh_testroot(1)

ensure that a package is built with necessary level of root permissions

dh_ucf(1)

register configuration files with ucf

dh_update_autotools_config(1)

Update autotools config files

dh_usrlocal(1)

migrate usr/local directories to maintainer scripts

DEBHELPER CONFIG FILES¶

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/package.foo (where package of course, is replaced with the package that is being acted on).

For example, dh_installdocs uses files named debian/package.docs 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/package.foo 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/package.foo.ARCH or debian/package.foo.OS 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 ignored.

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

SHARED DEBHELPER OPTIONS¶

The following command line options are supported by all debhelper programs.

-v, --verbose

Verbose mode: show commands that modify the package build directory.

Note that verbose mode may also output other "internal" commands that do not directly affect the package build directory.

--no-act

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.

--remaining-packages

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

--mainpackage=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/package.foo files.

-O=option|bundle

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.

COMMON DEBHELPER OPTIONS¶

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 excluded.

-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.

BUILD SYSTEM OPTIONS¶

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).

--max-parallel=maximum

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 support.

Notably, setting the maximum to 1 is effectively the same as using --no-parallel.

--reload-all-buildenv-variables

By default, dh(1) will compute several environment variables (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 $@
    override_dh_auto_configure:
        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.

COMPATIBILITY LEVELS¶

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, if only for selected commands, 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. To use this method, the debian/compat file 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~)

Note that you must use either the build-dependency on debhelper-compat or the debian/compat file. Whenever possible, the debhelper-compat build-dependency is recommended.

If needed be, the DH_COMPAT environment variable can be used to override the compat level for a given command. The feature is mostly useful for either temporarily upgrading a few commands to a new compat level or keeping a few commands on a lower compat level. The feature is best used sparingly as it effectively introduces special-cases into the debian/rules file that may be surprising to maintainers or reviewers (or, in the long term, to yourself).

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.

NOTES¶

  my $temp="set -e\nset -- @ARGV\n" . << 'EOF';
  #DEBHELPER#
  EOF
  if (system($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}");
     }
  }

ENVIRONMENT¶

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".

DH_VERBOSE

Set to a non-empty value to enable verbose mode. Please see the -v / --verbose option for details.

DH_QUIET

Set to a non-empty value 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 or -v / --verbose is passed.

DH_COMPAT

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.

DH_NO_ACT

Set to 1 to enable no-act mode.

DH_OPTIONS

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 DH_OPTIONS.

DH_ALWAYS_EXCLUDE

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 tree.

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 DH_ALWAYS_EXCLUDE=CVS:.svn

DH_EXTRA_ADDONS

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.

DH_COLORS, DPKG_COLORS

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.

NO_COLOR

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 <https://no-color.org/>. In this project, the environment variables (such as DH_COLORS) are considered an explicit request for color.

CFLAGS, CPPFLAGS, CXXFLAGS, OBJCFLAGS, OBJCXXFLAGS, GCJFLAGS, FFLAGS, FCFLAGS, LDFLAGS

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.

DEB_BUILD_OPTIONS

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).

DEB_BUILD_MAINT_OPTIONS

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.

SEE ALSO¶

debhelper-compat-upgrade-checklist(7)

List of supported compat levels and an upgrade checklist for each of them.

/usr/share/doc/debhelper/examples/

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

<http://joeyh.name/code/debhelper/>

Debhelper web site.

AUTHOR¶

Joey Hess <joeyh@debian.org>