HowTo: Use ctags with source code and deep directory hierarchy

a) Create shell script

cd $1
ctags *

b) Create tags file for each subdirectory:

find * -type d -exec ~/bin/ {} \;

c) Rebuild tag file for each directory, when working create keymap and save into ~/.vimrc:

nmap ,t :!(cd %:p:h;ctags *.[ch])&

d) Build global tag file:

cd ~/<project_dir> ctags --file-scope=no -R

e) Configure vim to read local tag file first, if not found, search global tag file:

:set tags=./tags,tags,~/project/tags