        Syntax:  /history  [ NUMBER ]

        PMF has a history list, inspired by csh.
        The number of commands to save on the history list is
        controlled by the variable "history".

        The command "history" will print the latest (NUMBER) commands.
        If PMF is compiled with the GNU readline library, you can use
        CTRL-P and CTRL-N to step up and down in the history list,

        If the variable "substitute_history" has the value true,
        you can also use history substitutions ("!!", "!number" or "!string").

        See also:  history, substitute_history, /perform
