DH(1) Debhelper DH(1)
NAME
dh - debhelper command sequencer
SYNOPSIS
dh sequence [--with addon[,addon ...]] [--list] [--until cmd] [--before cmd] [--after cmd] [--remaining] [debhelperoptions]
DESCRIPTION
dh runs a sequence of debhelper commands. The supported sequences correspond to the targets of a debian/rules file: build-arch, build-
indep, build, clean, install-indep, install-arch, install, binary-arch, binary-indep, and binary.
Commands in the build-indep, install-indep and binary-indep sequences are passed the -i option to ensure they only work on architecture
independent packages, and commands in the build-arch, install-arch and binary-arch sequences are passed the -a option to ensure they only
work on architecture dependent packages.
If debian/rules contains a target with a name like override_dh_command, then when it would normally run dh_command, dh will instead call
that target. The override target can then run the command with additional options, or run entirely different commands instead. See examples
below. (Note that to use this feature, you should Build-Depend on debhelper 7.0.50 or above.)
OPTIONS
--with addon[,addon ...]
Add the debhelper commands specified by the given addon to appropriate places in the sequence of commands that is run. This option can
be repeated more than once, or multiple addons can be listed, separated by commas. This is used when there is a third-party package
that provides debhelper commands. See the PROGRAMMING file for documentation about the sequence addon interface.
--without addon
The inverse of --with, disables using the given addon.
--list, -l
List all available addons.
--until cmd
Run commands in the sequence until and including cmd, then stop.
--before cmd
Run commands in the sequence before cmd, then stop.
--after cmd
Run commands in the sequence that come after cmd.
--remaining
Run all commands in the sequence that have yet to be run.
--no-act
Prints commands that would run for a given sequence, but does not run them.
All other options passed to dh are passed on to each command it runs. This can be used to set an option like -v or -X or -N, as well as for
more specialised options.
In the above options, cmd can be a full name of a debhelper command, or a substring. It'll first search for a command in the sequence
exactly matching the name, to avoid any ambiguity. If there are multiple substring matches, the last one in the sequence will be used.
EXAMPLES
To see what commands are included in a sequence, without actually doing anything:
dh binary-arch --no-act
This is a very simple rules file, for packages where the default sequences of commands work with no additional options.
#!/usr/bin/make -f
%:
dh $@
Often you'll want to pass an option to a specific debhelper command. The easy way to do with is by adding an override target for that
command.
#!/usr/bin/make -f
%:
dh $@
override_dh_strip:
dh_strip -Xfoo
override_dh_installdocs:
dh_installdocs README TODO
Sometimes the automated dh_auto_configure(1) and dh_auto_build(1) can't guess what to do for a strange package. Here's how to avoid running
either and instead run your own commands.
#!/usr/bin/make -f
%:
dh $@
override_dh_auto_configure:
./mondoconfig
override_dh_auto_build:
make universe-explode-in-delight
Another common case is wanting to do something manually before or after a particular debhelper command is run.
#!/usr/bin/make -f
%:
dh $@
override_dh_fixperms:
dh_fixperms
chmod 4755 debian/foo/usr/bin/foo
If your package is a Python package, dh will use dh_pysupport by default. This is how to use dh_pycentral instead.
#!/usr/bin/make -f
%:
dh $@ --with python-central
If your package uses autotools and you want to freshen config.sub and config.guess with newer versions from the autotools-dev package at
build time, you can use some commands provided in autotools-dev that automate it, like this.
#!/usr/bin/make -f
%:
dh $@ --with autotools_dev
Here is how to force use of Perl's Module::Build build system, which can be necessary if debhelper wrongly detects that the package uses
MakeMaker.
#!/usr/bin/make -f
%:
dh $@ --buildsystem=perl_build
To patch your package using quilt, you can tell dh to use quilt's dh sequence addons like this:
#!/usr/bin/make -f
%:
dh $@ --with quilt
Here is an example of overriding where the dh_auto_* commands find the package's source, for a package where the source is located in a
subdirectory.
#!/usr/bin/make -f
%:
dh $@ --sourcedirectory=src
And here is an example of how to tell the dh_auto_* commands to build in a subdirectory, which will be removed on clean.
#!/usr/bin/make -f
%:
dh $@ --builddirectory=build
If your package can be built in parallel, you can support parallel building as follows. Then dpkg-buildpackage -j will work.
#!/usr/bin/make -f
%:
dh $@ --parallel
Here is a way to prevent dh from running several commands that you don't want it to run, by defining empty override targets for each
command.
#!/usr/bin/make -f
%:
dh $@
# Commands not to run:
override_dh_auto_test override_dh_compress override_dh_fixperms:
Sometimes, you may need to make an override target only run commands when a particular package is being built. This can be accomplished
using dh_listpackages(1) to test what is being built. For example:
#!/usr/bin/make -f
%:
dh $@
override_dh_fixperms:
dh_fixperms
ifneq (,$(filter foo, $(shell dh_listpackages)))
chmod 4755 debian/foo/usr/bin/foo
endif
Finally, remember that you are not limited to using override targets in the rules file when using dh. You can also explicitly define any of
the regular rules file targets when it makes sense to do so. A common reason to do this is when your package needs different build-arch and
build-indep targets. For example, a package with a long document build process can put it in build-indep.
#!/usr/bin/make -f
%:
dh $@
build-indep:
$(MAKE) docs
build-arch:
$(MAKE) bins
Note that in the example above, dh will arrange for "debian/rules build" to call your build-indep and build-arch targets. You do not need
to explicitly define the dependencies in the rules file when using dh with compatability level v9. This example would be more complicated
with earlier compatability levels.
INTERNALS
If you're curious about dh's internals, here's how it works under the hood.
Each debhelper command will record when it's successfully run in debian/package.debhelper.log. (Which dh_clean deletes.) So dh can tell
which commands have already been run, for which packages, and skip running those commands again.
Each time dh is run, it examines the log, and finds the last logged command that is in the specified sequence. It then continues with the
next command in the sequence. The --until, --before, --after, and --remaining options can override this behavior.
A sequence can also run dependent targets in debian/rules. For example, the "binary" sequence runs the "install" target.
dh sets environment variables listed by dpkg-buildflags, unless they are already set. It supports DEB_BUILD_OPTIONS=noopt too.
dh uses the DH_INTERNAL_OPTIONS environment variable to pass information through to debhelper commands that are run inside override
targets. The contents (and indeed, existence) of this environment variable, as the name might suggest, is subject to change at any time.
SEE ALSO
debhelper(7)
This program is a part of debhelper.
AUTHOR
Joey Hess <joeyh@debian.org>
8.9.0ubuntu2.1 2012-06-12 DH(1)