../
[+] btr/
[+] buf/
[+] data/
[+] dict/
[+] eval/
[+] fil/
[+] fsp/
[+] fts/
[+] fut/
[+] gis/
[+] ha/
[+] handler/
[+] ibuf/
[+] include/
[+] lock/
[+] log/
[+] mach/
[+] mem/
[+] mtr/
[+] os/
[+] page/
[+] pars/
[+] que/
[+] read/
[+] rem/
[+] row/
[+] srv/
[+] sync/
[+] trx/
[+] ut/

What is this ?

This is an online code browser that allows you to browse C/C++ code just like in your IDE, with semantic highlighting and contextual tooltips that show you the usages and cross references.
Open a C or C++ file and try it by hovering over the symbols!
Or take the feature tour.