1 2 3 4 5 6 7 8 9 10 11 12 13
$ To the end of the line. 1 From start to end 2 From _ to end 3 From end to end 4 empty line \n 5 empty line \r\n 6 Spaces 7 Tabs 8 Backspace 9 Vertical tab 10 Form feed 11 Carriage return 12 Idempotent (count has no effect)