save proof output for later display with :pso or :pso!

(set-saved-output t t)    ; save proof output for later, but inhibit it now
(set-saved-output t :all) ; save proof output for later, but inhibit all
                          ;   output (except WARNING!, for critical warnings,
                          ;   and ERROR, unless these are already inhibited)
:set-saved-output t :all  ; same as the line above
(set-saved-output t nil)  ; save proof output for later, but print it now too
(set-saved-output nil t)  ; do not save proof output, and inhibit it
(set-saved-output nil nil); do not save proof output or inhibit output
(set-saved-output nil :same), (set-saved-output t :same)
                          ; save proof output or not, as indicated, but do
                          ;   not change which output is inhibited
(set-saved-output nil :normal)
                          ; the behavior when ACL2 first starts up: do not
                          ;   save output, and only inhibit proof-tree output
(set-saved-output t '(warning observation proof-tree prove))
                          ; save proof output for later, and inhibit the
                          ;   indicated kinds of output

General Form:
(set-saved-output save-flg inhibit-flg)
Parameter save-flg is t to cause output to be saved for later display using pso or pso!; see pso and see pso!, and see the documentation for proof-checker commands of the same names. Set save-flg to nil to turn off this feature; except, it always stays on in proof-checker sessions entered with verify. The other argument, inhibit-flg, controls whether output should be inhibited when it is created (normally, during a proof attempt). So a common combination is to set both arguments to t, to indicate that output should be suppressed for now but saved for printing with pso or pso!. The examples above give a good summary of the functionality for the second argument.

Saved output is cleared at the start of every event, and also at the start of every proof-checker commands that invoke the prover. Note that interactive proof-checker commands, that is, from a proof-checker session entered with verify, are always run with output saved.

Also see set-gag-mode; and see set-print-clause-ids, which causes subgoal numbers to be printed during proof attempts when output is inhibited.

See set-inhibit-output-lst if you want to inhibit certain output from the prover but not other output (e.g., not the summary), and you don't want to save any output.