欢迎大家赞助一杯啤酒🍺 我们准备了下酒菜:Formal mathematics/Isabelle/ML, Formal verification/Coq/Agda, C++/Erlang/Lisp
The grep command searches one or more input files for lines containing a match to a specified pattern. By default, grep prints the matching lines.
http://www.gnu.org/software/grep/