sed code example

Example 1: sed

-i
sed -i 's/#mode/mode/' file.txt
http://sed.sourceforge.net/sed1line.txt

 # substitute "foo" with "bar" ONLY for lines which contain "baz"
 sed '/baz/s/foo/bar/g' file.sh

Example 2: sed

sed 's/foo/bar/'
http://sed.sourceforge.net/sed1line.txt

Example 3: sed line

Use d option at the end of sed replace definition for deleting line of matches.
sed -i "" "s/matching_pattern/d" file.txt