10 Using a Development Shell
When debugging certain commands or even when just editing packages,
devshell can be a useful tool. When you invoke
tasks up to and including
do_patch are run for the
specified target. Then, a new terminal is opened and you are placed in
}, the source
directory. In the new terminal, all the OpenEmbedded build-related
environment variables are still defined so you can use commands such as
make. The commands execute just as if the
OpenEmbedded build system were executing them. Consequently, working
this way can be helpful when debugging a build or preparing software to
be used with the OpenEmbedded build system.
Following is an example that uses
devshell on a target named
$ bitbake matchbox-desktop -c devshell
This command spawns a terminal with a shell prompt within the OpenEmbedded build environment. The OE_TERMINAL variable controls what type of shell is opened.
For spawned terminals, the following occurs:
PATHvariable includes the cross-toolchain.
pkgconfigvariables find the correct
configurecommand finds the Yocto Project site files as well as any other necessary files.
Within this environment, you can run configure or compile commands as if they were being run by the OpenEmbedded build system itself. As noted earlier, the working directory also automatically changes to the Source Directory (S).
To manually run a specific task using
devshell, run the
run.* script in the
run.do_configure.pid). If a task’s script does
not exist, which would be the case if the task was skipped by way of the
sstate cache, you can create the task by first running it outside of the
$ bitbake -c task
Execution of a task’s
run.*script and BitBake’s execution of a task are identical. In other words, running the script re-runs the task just as it would be run using the
run.*file that does not have a
.pidextension is a symbolic link (symlink) to the most recent version of that file.
Remember, that the
devshell is a mechanism that allows you to get
into the BitBake task execution environment. And as such, all commands
must be called just as BitBake would call them. That means you need to
provide the appropriate options for cross-compilation and so forth as
When you are finished using
devshell, exit the shell or close the
It is worth remembering that when using
devshellyou need to use the full compiler name such as
arm-poky-linux-gnueabi-gccinstead of just using
gcc. The same applies to other applications such as
libtooland so forth. BitBake sets up environment variables such as CC to assist applications, such as
maketo find the correct tools.
It is also worth noting that
devshellstill works over X11 forwarding and similar situations.