A quick summary on what are tags and how to create them
find . -name \*.\*pp | xargs etags
create the tags from *.*pp files, including .cpp and .hpp. With the tags file, you can do “esc .” on the current function or variable and find its definition.
To go back to the original location, do esc *
To get multiple patterns of files that we want to generate tags for
find . -name “*.hh” -o -name “*.C” (for *.hh an *.C)
2. “xargs” just pipe in the stdin arguments
3. A documentation on tags for emacs