-b Number the non-blank output lines, starting at 1. -e Display non-printing characters (see the -v option), and display a dollar sign (`$') at the end of each line. -n Number the output lines, starting at 1. -s Squeeze multiple adjacent empty lines, causing the output to be single spaced. -t Display non-printing characters (see the -v option), and display tab characters as `^I'. -u The -u option guarantees that the output is unbuffered. -v Display non-printing characters so they are visible.
