ファイル閲覧ツール less v290
     Less is a program similar to  more  (1),  but  which  allows
     backward  movement  in the file as well as forward movement.
     Also, less does not have  to  read  the  entire  input  file
     before starting, so with large input files it starts up fas-
     ter than text editors like vi (1).  Less  uses  termcap  (or
     terminfo  on  some  systems),  so it can run on a variety of
     terminals.  There is even limited support for hardcopy  ter-
     minals.   (On  a  hardcopy  terminal,  lines which should be
     printed at the top of the screen are prefixed with a caret.)
     Commands are based on both more and vi. Commands may be pre-
     ceded  by  a  decimal  number,  called N in the descriptions
     below.  The number is used by some commands, as indicated.