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+++ b/poky/documentation/overview-manual/concepts.rst
@@ -2189,3 +2189,173 @@ For more information, see the
BitBake User Manual. You can also reference the "`Why Not
Fakeroot? <https://github.com/wrpseudo/pseudo/wiki/WhyNotFakeroot>`__"
article for background information on Fakeroot and Pseudo.
+
+BitBake Tasks Map
+=================
+
+To understand how BitBake operates in the build directory and environment
+we can consider the following recipes and diagram, to have full picture
+about the tasks that BitBake runs to generate the final package file
+for the recipe.
+
+We will have two recipes as an example:
+
+- ``libhello``: A recipe that provides a shared library
+- ``sayhello``: A recipe that uses ``libhello`` library to do its job
+
+.. note::
+
+ ``sayhello`` depends on ``libhello`` at compile time as it needs the shared
+ library to do the dynamic linking process. It also depends on it at runtime
+ as the shared library loader needs to find the library.
+ For more details about dependencies check :ref:`ref-varlocality-recipe-dependencies`.
+
+``libhello`` sources are as follows:
+
+- ``LICENSE``: This is the license associated with this library
+- ``Makefile``: The file used by ``make`` to build the library
+- ``hellolib.c``: The implementation of the library
+- ``hellolib.h``: The C header of the library
+
+``sayhello`` sources are as follows:
+
+- ``LICENSE``: This is the license associated with this project
+- ``Makefile``: The file used by ``make`` to build the project
+- ``sayhello.c``: The source file of the project
+
+Before presenting the contents of each file, here are the steps
+that we need to follow to accomplish what we want in the first place,
+which is integrating ``sayhello`` in our root file system:
+
+#. Create a Git repository for each project with the corresponding files
+
+#. Create a recipe for each project
+
+#. Make sure that ``sayhello`` recipe :term:`DEPENDS` on ``libhello``
+
+#. Make sure that ``sayhello`` recipe :term:`RDEPENDS` on ``libhello``
+
+#. Add ``sayhello`` to :term:`IMAGE_INSTALL` to integrate it into
+ the root file system
+
+The following are the contents of ``libhello/Makefile``::
+
+ LIB=libhello.so
+
+ all: $(LIB)
+
+ $(LIB): hellolib.o
+ $(CC) $< -Wl,-soname,$(LIB).1 -fPIC $(LDFLAGS) -shared -o $(LIB).1.0
+
+ %.o: %.c
+ $(CC) -c $<
+
+ clean:
+ rm -rf *.o *.so*
+
+.. note::
+
+ When creating shared libraries, it is strongly recommended to follow the Linux
+ conventions and guidelines (see `this article
+ <https://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html>`__
+ for some background).
+
+.. note::
+
+ When creating ``Makefile`` files, it is strongly recommended to use ``CC``, ``LDFLAGS``
+ and ``CFLAGS`` as BitBake will set them as environment variables according
+ to your build configuration.
+
+The following are the contents of ``libhello/hellolib.h``::
+
+ #ifndef HELLOLIB_H
+ #define HELLOLIB_H
+
+ void Hello();
+
+ #endif
+
+The following are the contents of ``libhello/hellolib.c``::
+
+ #include <stdio.h>
+
+ void Hello(){
+ puts("Hello from a Yocto demo \n");
+ }
+
+The following are the contents of ``sayhello/Makefile``::
+
+ EXEC=sayhello
+ LDFLAGS += -lhello
+
+ all: $(EXEC)
+
+ $(EXEC): sayhello.c
+ $(CC) $< $(LDFLAGS) $(CFLAGS) -o $(EXEC)
+
+ clean:
+ rm -rf $(EXEC) *.o
+
+The following are the contents of ``sayhello/sayhello.c``::
+
+ #include <hellolib.h>
+
+ int main(){
+ Hello();
+ return 0;
+ }
+
+The following are the contents of ``libhello_0.1.bb``::
+
+ SUMMARY = "Hello demo library"
+ DESCRIPTION = "Hello shared library used in Yocto demo"
+
+ # NOTE: Set the License according to the LICENSE file of your project
+ # and then add LIC_FILES_CHKSUM accordingly
+ LICENSE = "CLOSED"
+
+ # Assuming the branch is main
+ # Change <username> accordingly
+ SRC_URI = "git://github.com/<username>/libhello;branch=main;protocol=https"
+
+ S = "${WORKDIR}/git"
+
+ do_install(){
+ install -d ${D}${includedir}
+ install -d ${D}${libdir}
+
+ install hellolib.h ${D}${includedir}
+ oe_soinstall ${PN}.so.${PV} ${D}${libdir}
+ }
+
+The following are the contents of ``sayhello_0.1.bb``::
+
+ SUMMARY = "SayHello demo"
+ DESCRIPTION = "SayHello project used in Yocto demo"
+
+ # NOTE: Set the License according to the LICENSE file of your project
+ # and then add LIC_FILES_CHKSUM accordingly
+ LICENSE = "CLOSED"
+
+ # Assuming the branch is main
+ # Change <username> accordingly
+ SRC_URI = "git://github.com/<username>/sayhello;branch=main;protocol=https"
+
+ DEPENDS += "libhello"
+ RDEPENDS:${PN} += "libhello"
+
+ S = "${WORKDIR}/git"
+
+ do_install(){
+ install -d ${D}/usr/bin
+ install -m 0700 sayhello ${D}/usr/bin
+ }
+
+After placing the recipes in a custom layer we can run ``bitbake sayhello``
+to build the recipe.
+
+The following diagram shows the sequences of tasks that BitBake
+executes to accomplish that.
+
+.. image:: svg/bitbake_tasks_map.*
+ :width: 100%