Any given recipe consists of a set of tasks.
The standard BitBake behavior in most cases is:
do_fetch
,
do_unpack
,
do_patch
,
do_configure
,
do_compile
,
do_install
,
do_package
,
do_package_write_*
, and
do_build
.
The default task is do_build
and any tasks
on which it depends build first.
Some tasks, such as do_devshell
, are not
part of the default build chain.
If you wish to run a task that is not part of the default build
chain, you can use the -c
option in
BitBake.
Here is an example:
$ bitbake matchbox-desktop -c devshell
The -c
option respects task dependencies,
which means that all other tasks (including tasks from other
recipes) that the specified task depends on will be run before
the task.
Even when you manually specify a task to run with
-c
, BitBake will only run the task if it
considers it "out of date".
See the
"Stamp Files and the Rerunning of Tasks"
section in the Yocto Project Overview and Concepts Manual for
how BitBake determines whether a task is "out of date".
If you want to force an up-to-date task to be rerun (e.g.
because you made manual modifications to the recipe's
WORKDIR
that you want to try out), then you can use the
-f
option.
-f
is never required when
running the
do_devshell
task is because the
[
nostamp
]
variable flag is already set for the task.
The following example shows one way you can use the
-f
option:
$ bitbake matchbox-desktop . . make some changes to the source code in the work directory . . $ bitbake matchbox-desktop -c compile -f $ bitbake matchbox-desktop
This sequence first builds and then recompiles
matchbox-desktop
.
The last command reruns all tasks (basically the packaging
tasks) after the compile.
BitBake recognizes that the do_compile
task was rerun and therefore understands that the other tasks
also need to be run again.
Another, shorter way to rerun a task and all
normal recipe build tasks
that depend on it is to use the -C
option.
-c
option, which is lower-cased.
Using this option invalidates the given task and then runs the
do_build
task, which is the default task if no task is given, and the
tasks on which it depends.
You could replace the final two commands in the previous example
with the following single command:
$ bitbake matchbox-desktop -C compile
Internally, the -f
and
-C
options work by tainting (modifying) the
input checksum of the specified task.
This tainting indirectly causes the task and its
dependent tasks to be rerun through the normal task dependency
mechanisms.
WARNING: /home/ulf/poky/meta/recipes-sato/matchbox-desktop/matchbox-desktop_2.1.bb.do_compile is tainted from a forced runThe purpose of the warning is to let you know that the work directory and build output might not be in the clean state they would be in for a "normal" build, depending on what actions you took. To get rid of such warnings, you can remove the work directory and rebuild the recipe, as follows:
$ bitbake matchbox-desktop -c clean $ bitbake matchbox-desktop
You can view a list of tasks in a given package by running the
do_listtasks
task as follows:
$ bitbake matchbox-desktop -c listtasks
The results appear as output to the console and are also in the
file ${WORKDIR}/temp/log.do_listtasks
.