Command - SED

Command - SED

Insert the # sign from a specific line to the last
# sed -i '4,$ s/^/#/' file-name.sh
Add special sign with sed
# sed -i -e 's/$/ \&>> $STATUS/g' file-name.sh
Add Variable with sed
# sed -i 's/&> $STATUS//g' file-name.sh

Web tools

http://rubular.com/
http://rubyxp.com/

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions?redirectlocale=en-US&redirectslug=JavaScript%2FGuide%2FRegular_Expressions