debhelper(7)
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.
DEBHELPER COMMANDS
Here is the list of debhelper commands you can use. See their man pages
for additional documentation.
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_fixperms(1)
fix permissions of files in package build directories
dh_gconf(1)
install GConf defaults files and register schemas
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_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_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_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_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 as root
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
Deprecated Commands
A few debhelper commands are deprecated and should not be used.
dh_installmanpages(1)
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.
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. 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. If you prefer power and complexity, you can make the file executable, and write a program that outputs whatever content is appropriate for a given situation. When you do so, the output is not further processed to expand wildcards or strip comments.
SHARED DEBHELPER OPTIONS
The following command line options are supported by all debhelper
programs.
-v, --verbose
Verbose mode: show all commands that modify 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.
-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.
--ignore=file
Ignore the specified file. This can be used if debian/ contains a
debhelper config file that a debhelper command should not act on.
Note that debian/compat, debian/control, and debian/changelog can't
be ignored, but then, there should never be a reason to ignore
those files.
For example, if upstream ships a debian/init that you don't want
dh_installinit to install, use --ignore=debian/init
-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 \fIitem\fR 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. -Ddirectory, --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. -B[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 unncessary 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. --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. The
compatibility level is specified in the debian/compat file and the file
must be present.
Tell debhelper what compatibility level to use by writing a number to
debian/compat. For example, to use v9 mode:
% echo 9 > debian/compat
Your package will also need a versioned build dependency on a version
of debhelper equal to (or greater than) the compatibility level your
package uses. So for compatibility level 9, ensure debian/control has:
Build-Depends: debhelper (>= 9)
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.
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 scripts.
- 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
there.
- 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 Makefile.PL.
This mode is deprecated.
v9 Changes from v8 are:
- Multiarch support. In particular, dh_auto_configure passes
multiarch directories to autoconf in --libdir and
--libexecdir.
- 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
- 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.
v10 This is the recommended mode of operation.
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 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.
- 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.
- 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 did.
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:
override_dh_foo:
dh_foo -pmy-pkg
override_dh_bar:
dh_bar
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 package.
v11 This compatibility level is still open for development; use with
caution.
Changes from v10 are:
- dh_installmenu no longer installs menu files. The menu-
method files are still installed.
- The -s (--same-arch) option is removed.
- Invoking dh_clean -k now causes an error instead of a
deprecation warning.
- dh_installdocs now installs user-supplied documentation
(e.g. debian/package.docs) into /usr/share/doc/mainpackage
rather than /usr/share/doc/package by default as
recommended by Debian Policy 3.9.7.
If you need the old behaviour, it can be emulated by using
the --mainpackage option.
Please remember to check/update your doc-base files.
- 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 change.
Participating in the open beta testing of new compat levels
It is possible to opt-in to the open beta testing of new compat levels.
This is done by setting the compat level to the string "beta-tester".
Packages using this compat level will automatically be upgraded to the
highest compatibility level in open beta. In periods without any open
beta versions, the compat level will be the highest stable
compatibility level.
Please consider the following before opting in:
* The automatic upgrade in compatibility level may cause the package
(or a feature in it) to stop functioning.
* Compatibility levels in open beta are still subject to change. We
will try to keep the changes to a minimal once the beta starts.
However, there are no guarantees that the compat will not change
during the beta.
* We will notify you via debian-devel@lists.debian.org before we
start a new open beta compat level. However, once the beta starts
we expect that you keep yourself up to date on changes to
debhelper.
* The "beta-tester" compatibility version in unstable and testing
will often be different than the one in stable-backports.
Accordingly, it is not recommended for packages being backported
regularly.
* You can always opt-out of the beta by resetting the compatibility
level of your package to a stable version.
Should you still be interested in the open beta testing, please run:
% echo beta-tester > debian/compat
You will also need to ensure that debian/control contains:
Build-Depends: debhelper (>= 9.20160815~)
To ensure that debhelper knows about the "beta-tester" compat level.
NOTES
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 <https://wiki.debian.org/BuildProfileSpec>.
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
dh_installdeb.
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 $temp="set -e\nset -- @ARGV\n" . << 'EOF';
#DEBHELPER#
EOF
if (system($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}");
}
}
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.
udebs
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.
ENVIRONMENT
The following environment variables can influence the behavior of
debhelper. It is important to note that these must be actual
environment variables in order to function properly (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 1 to enable verbose mode. Debhelper will output every
command it runs. Also enables verbose build logs for some build
systems like autoconf.
DH_QUIET
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.
DH_COMPAT
Temporarily specifies what compatibility level debhelper should run
at, overriding any value in debian/compat.
DH_NO_ACT
Set to 1 to enable no-act mode.
DH_OPTIONS
Anything in this variable will be prepended to the command line
arguments of all debhelper commands.
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
SEE ALSO
/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>
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Education
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Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
