Logging information during task execution
The logging utilities provided by BitBake are very useful for tracing the code execution path. BitBake provides logging functions for use in Python and Shell Script code, described as follows:
- Python: For use within Python functions, BitBake supports several log levels, which are 
bb.fatal,bb.error,bb.warn,bb.note,bb.plain, andbb.debug - Shell Script: For use in Shell Script functions, the same set of log levels exists and is accessed with a similar syntax: 
bbfatal,bberror,bbwarn,bbnote,bbplain, andbbdebug 
These logging functions are very similar to each other but have inner differences, described as follows:
bb.fatalandbbfatal: These have the highest priority of logging messages as they print the message and terminate the processing. They cause the build to be interrupted.bb.errorandbberror: These are used to display an error but do not force the build to stop.bb.warnandbbwarn: These are used to warn users about something.bb.noteandbbnote...