============= The first line, no empty lines before second line third line 4th line last line, no lines after ------------- There is no such file ============= 1 2 3 ------------- 2 3 9 ------------- 1 6 9 ------------- 1 9 9 ============= 1 3 5 7 ------------- 3 5 ------------- ------------- 5 ============= hghghghg does not exist ------------- No pattern pattern ABC pattern ABC pattern ABC ABC ABC ABC no pattern ============