Syntax: HISTORY [-]

   HISTORY lists up to the the last eighty commands issued, giving
each an identifying number. HISTORY - lists the commands backwards,
which is probably what you want if you are thinking of the history
list as a macro (see HELP all)

   The SM history feature is similar to that in the Unix
C-shell, but using the character ^ instead of !. It also has a
sort-of-emacs history editor, which works closely with the ^-system.
See EDITOR for details.

   Each command can be re-used by referring to it by its number as
^nn, or by giving a unique abbreviation as ^abbrev. As a special case,
the previous command may be repeated as ^^ and the last word of the
last command as ^$. These symbols are white-space delimited, and are
expanded as soon as possible. For example a ^^ will be immediately
replaced by the text of the previous command, and ^^<CR> will execute
it.  Sometimes a ^string search will get a more recent command than
the one that you wanted, in this case use ^R (reverse search) instead.
The history character need not be ^, you can rebind it to anything
(its name is history_char).  You might also want to rebind ^ to be a
simple ^.

   These commands are written to a file in the current directory at
the end of a session, and read from that file at the beginning of the
next.  This file's name is given by the "save_file" entry in the
environment (.sm) file, if it is absent, no history is saved.  The
number of commands saved (default 80) can be set by the "history"
entry in the environment file.