sed 4.8-1
The sed (Stream EDitor) editor is a stream or batch (non-interactive) editor.
Sed takes text as input, performs an operation or set of operations on the text
and outputs the modified text.
The operations that sed performs
(substitutions, deletions, insertions, etc.) can be specified in a script file
or from the command line.
Website: http://www.gnu.org/software/sed