1DH(1) Debhelper DH(1)
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6 dh - debhelper command sequencer
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9 dh sequence [--with addon[,addon ...]] [--list] [debhelperĀ options]
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12 dh runs a sequence of debhelper commands. The supported sequences
13 correspond to the targets of a debian/rules file: build-arch, build-
14 indep, build, clean, install-indep, install-arch, install, binary-arch,
15 binary-indep, and binary.
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18 A debian/rules file using dh can override the command that is run at
19 any step in a sequence, by defining an override target.
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21 To override dh_command, add a target named override_dh_command to the
22 rules file. When it would normally run dh_command, dh will instead call
23 that target. The override target can then run the command with
24 additional options, or run entirely different commands instead. See
25 examples below.
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27 Override targets can also be defined to run only when building
28 architecture dependent or architecture independent packages. Use
29 targets with names like override_dh_command-arch and
30 override_dh_command-indep. (Note that to use this feature, you should
31 Build-Depend on debhelper 8.9.7 or above.)
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34 --with addon[,addon ...]
35 Add the debhelper commands specified by the given addon to
36 appropriate places in the sequence of commands that is run. This
37 option can be repeated more than once, or multiple addons can be
38 listed, separated by commas. This is used when there is a third-
39 party package that provides debhelper commands. See the PROGRAMMING
40 file for documentation about the sequence addon interface.
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42 A Build-Depends relation on the package dh-sequence-addon implies a
43 --with addon. This avoids the need for an explicit --with in
44 debian/rules that only duplicates what is already declared via the
45 build dependencies in debian/control. The relation can (since
46 12.5) be made optional via e.g. build-profiles. This enables you
47 to easily disable an addon that is only useful with certain
48 profiles (e.g. to facilitate bootstraping).
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50 Since debhelper 12.5, addons can also be activated in indep-only
51 mode (via Build-Depends-Indep) or arch-only mode (via Build-
52 Depends-Arch). Such addons are only active in the particular
53 sequence (e.g. binary-indep) which simplifies dependency management
54 for cross-builds.
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56 Please note that addons activated via Build-Depends-Indep or Build-
57 Depends-Arch are subject to additional limitations to ensure the
58 result is deterministic even when the addon is unavailable (e.g.
59 during clean). This implies that some addons are incompatible with
60 these restrictions and can only be used via Build-Depends (or
61 manually via debian/rules). Currently, such addons can only add
62 commands to sequences.
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64 --without addon
65 The inverse of --with, disables using the given addon. This option
66 can be repeated more than once, or multiple addons to disable can
67 be listed, separated by commas.
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69 --list, -l
70 List all available addons.
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72 When called only with this option, dh can be called from any
73 directory (i.e. it does not need access to files from a source
74 package).
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76 --no-act
77 Prints commands that would run for a given sequence, but does not
78 run them.
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80 Note that dh normally skips running commands that it knows will do
81 nothing. With --no-act, the full list of commands in a sequence is
82 printed.
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84 Other options passed to dh are passed on to each command it runs. This
85 can be used to set an option like -v or -X or -N, as well as for more
86 specialised options.
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89 To see what commands are included in a sequence, without actually doing
90 anything:
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92 dh binary-arch --no-act
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94 This is a very simple rules file, for packages where the default
95 sequences of commands work with no additional options.
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97 #!/usr/bin/make -f
98 %:
99 dh $@
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101 Often you'll want to pass an option to a specific debhelper command.
102 The easy way to do with is by adding an override target for that
103 command.
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105 #!/usr/bin/make -f
106 %:
107 dh $@
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109 override_dh_strip:
110 dh_strip -Xfoo
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112 override_dh_auto_configure:
113 dh_auto_configure -- --with-foo --disable-bar
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115 Sometimes the automated dh_auto_configure(1) and dh_auto_build(1) can't
116 guess what to do for a strange package. Here's how to avoid running
117 either and instead run your own commands.
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119 #!/usr/bin/make -f
120 %:
121 dh $@
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123 override_dh_auto_configure:
124 ./mondoconfig
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126 override_dh_auto_build:
127 make universe-explode-in-delight
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129 Another common case is wanting to do something manually before or after
130 a particular debhelper command is run.
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132 #!/usr/bin/make -f
133 %:
134 dh $@
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136 override_dh_fixperms:
137 dh_fixperms
138 chmod 4755 debian/foo/usr/bin/foo
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140 Python tools are not run by dh by default, due to the continual change
141 in that area. Here is how to use dh_python2.
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143 #!/usr/bin/make -f
144 %:
145 dh $@ --with python2
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147 Here is how to force use of Perl's Module::Build build system, which
148 can be necessary if debhelper wrongly detects that the package uses
149 MakeMaker.
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151 #!/usr/bin/make -f
152 %:
153 dh $@ --buildsystem=perl_build
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155 Here is an example of overriding where the dh_auto_* commands find the
156 package's source, for a package where the source is located in a
157 subdirectory.
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159 #!/usr/bin/make -f
160 %:
161 dh $@ --sourcedirectory=src
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163 And here is an example of how to tell the dh_auto_* commands to build
164 in a subdirectory, which will be removed on clean.
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166 #!/usr/bin/make -f
167 %:
168 dh $@ --builddirectory=build
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170 If your package can be built in parallel, please either use compat 10
171 or pass --parallel to dh. Then dpkg-buildpackage -j will work.
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173 #!/usr/bin/make -f
174 %:
175 dh $@ --parallel
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177 If your package cannot be built reliably while using multiple threads,
178 please pass --no-parallel to dh (or the relevant dh_auto_* command):
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180 #!/usr/bin/make -f
181 %:
182 dh $@ --no-parallel
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184 Here is a way to prevent dh from running several commands that you
185 don't want it to run, by defining empty override targets for each
186 command.
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188 #!/usr/bin/make -f
189 %:
190 dh $@
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192 # Commands not to run:
193 override_dh_auto_test override_dh_compress override_dh_fixperms:
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195 A long build process for a separate documentation package can be
196 separated out using architecture independent overrides. These will be
197 skipped when running build-arch and binary-arch sequences.
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199 #!/usr/bin/make -f
200 %:
201 dh $@
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203 override_dh_auto_build-indep:
204 $(MAKE) -C docs
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206 # No tests needed for docs
207 override_dh_auto_test-indep:
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209 override_dh_auto_install-indep:
210 $(MAKE) -C docs install
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212 Adding to the example above, suppose you need to chmod a file, but only
213 when building the architecture dependent package, as it's not present
214 when building only documentation.
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216 override_dh_fixperms-arch:
217 dh_fixperms
218 chmod 4755 debian/foo/usr/bin/foo
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221 If you're curious about dh's internals, here's how it works under the
222 hood.
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224 In compat 10 (or later), dh creates a stamp file
225 debian/debhelper-build-stamp after the build step(s) are complete to
226 avoid re-running them. It is possible to avoid the stamp file by
227 passing --without=build-stamp to dh. This makes "no clean" builds
228 behave more like what some people expect at the expense of possibly
229 running the build and test twice (the second time as root or under
230 fakeroot(1)).
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232 Inside an override target, dh_* commands will create a log file
233 debian/package.debhelper.log to keep track of which packages the
234 command(s) have been run for. These log files are then removed once
235 the override target is complete.
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237 In compat 9 or earlier, each debhelper command will record when it's
238 successfully run in debian/package.debhelper.log. (Which dh_clean
239 deletes.) So dh can tell which commands have already been run, for
240 which packages, and skip running those commands again.
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242 Each time dh is run (in compat 9 or earlier), it examines the log, and
243 finds the last logged command that is in the specified sequence. It
244 then continues with the next command in the sequence.
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246 A sequence can also run dependent targets in debian/rules. For
247 example, the "binary" sequence runs the "install" target.
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249 dh uses the DH_INTERNAL_OPTIONS environment variable to pass
250 information through to debhelper commands that are run inside override
251 targets. The contents (and indeed, existence) of this environment
252 variable, as the name might suggest, is subject to change at any time.
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254 Commands in the build-indep, install-indep and binary-indep sequences
255 are passed the -i option to ensure they only work on architecture
256 independent packages, and commands in the build-arch, install-arch and
257 binary-arch sequences are passed the -a option to ensure they only work
258 on architecture dependent packages.
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261 debhelper(7)
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263 This program is a part of debhelper.
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266 Joey Hess <joeyh@debian.org>
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27012.6.1 2019-10-08 DH(1)