Cscope

I was first introduced to cscope through my job at Cisco. At that time, I never cared much about it. But now I realize it's one of the major productivity enhancement tools where source navigation through a pile of code written by many other people is concerned.

http://cscope.sourceforge.net/

This document provides a tutorial on how to set up cscope for large projects, using the example of the linux kernel.

http://cscope.sourceforge.net/large_projects.html

And this document teaches how to use cscope very efficiently from within vim.
http://cscope.sourceforge.net/cscope_vim_tutorial.html

Also, there are many other frontends to csope besides the simple ncurses based one. Try kscope.

http://kscope.sourceforge.net/

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