Applying a patch

For cases where we need to apply a patch to an existing package, we should use FILESEXTRAPATHS, which includes new directories in the searching algorithm, making the additional file visible to BitBake, as shown here:

Figure 13.4 – The content of .bbappend is used only to apply mypatch.patch

In the preceding example, THISDIR expands to the current directory, and PN and PV expand to the package name and version, respectively. This new path is then included in the directories list used for file searching. The prepend operator is crucial as it guarantees that the file is picked from this directory, even if a file with the same name is added in the lower priority layers in the future.

BitBake assumes that every file with a .patch or .diff extension is a patch and applies them accordingly.