EDITING FILES IN PLACE - ED RULES

http://stackoverflow.com/questions/12696125/sed-edit-the-file-in-place

http://wiki.bash-hackers.org/howto/edit-ed

http://www.gnu.org/software/ed/manual/ed_manual.html

echo "g/${MY_COOL_STRING}/d;w" | tr \; '\012' | ed -s ${MY_COOL_FILE}