Get started. Tumblr. Twitter. Facebook. Sed tip: Remove / Delete All Leading Blank Spaces / Tabs ( whitespace ) From Each Line. The sed (Stream Editor) is very powerful tool.
Each line of input is copied into a pattern space. You can run editing commands on each input line to delete or change the input. For example, delete lines containing word DVD, enter: cat input.txt | sed '/DVD/d' To Print the lines between each pair of words pen and pencil, inclusive, enter: $ cat input.txt sed -e '/^PEN/,/^PENCIL/p'