The prompt printed by ld
The prompt printed by ACL2 conveys information about various ``modes.'' See default-print-prompt and see ld-prompt for details.
The prompt during raw Lisp breaks is, with most Common Lisp
implementations, adjusted by ACL2 to include the string
(install-new-raw-prompt) ; install prompt with [RAW LISP] as described above (install-old-raw-prompt) ; revert to original prompt from host Common Lisp