1.7 Command-line-editing
Command-line editing and command history are supported using either an
external gnu readline library, an external BSD libedit library,  or a
built-in equivalent.  This choice is a configuration option at the time
gnuplot is built.
The editing commands of the built-in version are given below. The gnu
readline and BSD libedit libraries have their own documentation.
|  |       ^B    moves back a single character.
      ^F    moves forward a single character.
      ^A    moves to the beginning of the line.
      ^E    moves to the end of the line.
      ^H    and DEL delete the previous character.
      ^D    deletes the current character.
      ^K    deletes from current position to the end of line.
      ^L,^R redraws line in case it gets trashed.
      ^U    deletes the entire line.
      ^W    deletes from the current word to the end of line.
 | 
|  |       ^P    moves back through history.
      ^N    moves forward through history.
 |