../
[+] altq/
[+] arch/
[+] coda/
[+] compat/
[+] conf/
[+] crypto/
[+] ddb/
[+] dev/
[+] external/
[+] fs/
[+] kern/
[+] lib/
[+] miscfs/
[+] net/
[+] net80211/
[+] netatalk/
[+] netbt/
[+] netinet/
[+] netinet6/
[+] netipsec/
[+] netmpls/
[+] netsmb/
[+] nfs/
[+] opencrypto/
[+] secmodel/
[+] sys/
[+] ufs/
[+] uvm/

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.