Syntax: SAVE [ filename ]

   Save all the current macros, variables, and vectors in file
`filename' (if omitted the default is to use the value of `save_file'
in your .sm file, or failing that `sm.dmp'). The current history
buffer is also saved, as the macro `all'. Variables and vectors whose
names start with an `_' are not saved (they are assumed to be
temporaries), and neither are macros which start `##' (they are
assumed to be system macros).

   The opposite to SAVE is RESTORE (q.v.). You may want to use the
MACRO DELETE WORD command to undefine macros from e.g. the `default'
macro file.  See, for example, the macro `sav'.

   If verbose (q.v.) is greater than 0, some extra information is printed.