Google code search

Syntax and Examples (more about regexp syntax)
regexp Search for a regular expression
go{2}gle hello,\ world ^int printk
"exact string" Search for exact string
"compiler happy"
class:regexp function:regexp Search only in class and function names New!
class:BTree function:laugh
class:hash.*multimap function:.*range
file:regexp Search only in files or directories matching regexp
file:\.js$ XMLHttpRequest file:include/ ioctl
file:/usr/sys/ken/slp.c "You are not expected to understand this."
package:regexp Search packages with names matching regexp.
(A package's name is its URL or CVS server information.)
package:perl.*\.tar\.gz Frodo package:linux-2.6 int\ printk
lang:regexp Search only for programs written in languages matching regexp
lang:lisp xml lang:"c++" sprintf.*%s
license:regexp Search only for files with licenses matching regexp.
license:bsd int\ printf -license:gpl heapsort