The OpenEmbedded build system uses BitBake to generate the
Software Development Kit (SDK) installer script for both the
standard and extensible SDKs:
Note
For more information on the cross-development toolchain generation, see the "Cross-Development Toolchain Generation" section. For information on advantages gained when building a cross-development toolchain using thedo_populate_sdk
task, see the
"Building an SDK Installer"
section in the Yocto Project Application Development and the
Extensible Software Development Kit (SDK) manual.
Like image generation, the SDK script process consists of
several stages and depends on many variables.
The do_populate_sdk and
do_populate_sdk_ext tasks use these
key variables to help create the list of packages to actually
install.
For information on the variables listed in the figure, see the
"Application Development SDK"
section.
The do_populate_sdk task helps create
the standard SDK and handles two parts: a target part and a
host part.
The target part is the part built for the target hardware and
includes libraries and headers.
The host part is the part of the SDK that runs on the
SDKMACHINE.
The do_populate_sdk_ext task helps create
the extensible SDK and handles host and target parts
differently than its counter part does for the standard SDK.
For the extensible SDK, the task encapsulates the build system,
which includes everything needed (host and target) for the SDK.
Regardless of the type of SDK being constructed, the
tasks perform some cleanup after which a cross-development
environment setup script and any needed configuration files
are created.
The final output is the Cross-development
toolchain installation script (.sh file),
which includes the environment setup script.