plan9-grep.1 -q %27%5Eoption%27 file %26%26 sed -i %27s%2F%5Eoption.%2A%2Foption%3Dvalue%2F%27 file %7C%7C echo %27option%3Dvalue%27 %3E%3E file 
search a file for a pattern
source manpages: plan9-grep