┌─[phoe][phoetower][~] └─▪ sbcl --disable-debugger --eval "(error \"42\")" This is SBCL 2.0.4.debian, an implementation of ANSI Common Lisp. More information about SBCL is available at . SBCL is free software, provided as is, with absolutely no warranty. It is mostly in the public domain; some portions are provided under BSD-style licenses. See the CREDITS and COPYING files in the distribution for more information. Unhandled SIMPLE-ERROR in thread #: 42 Backtrace for: # 0: (SB-DEBUG::DEBUGGER-DISABLED-HOOK # # :QUIT T) 1: (SB-DEBUG::RUN-HOOK *INVOKE-DEBUGGER-HOOK* #) 2: (INVOKE-DEBUGGER #) 3: (ERROR "42") 4: (SB-INT:SIMPLE-EVAL-IN-LEXENV (ERROR "42") #) 5: (EVAL (ERROR "42")) 6: (SB-IMPL::PROCESS-EVAL/LOAD-OPTIONS ((:EVAL . "(error \"42\")"))) 7: (SB-IMPL::TOPLEVEL-INIT) 8: ((FLET SB-UNIX::BODY :IN SAVE-LISP-AND-DIE)) 9: ((FLET "WITHOUT-INTERRUPTS-BODY-14" :IN SAVE-LISP-AND-DIE)) 10: ((LABELS SB-IMPL::RESTART-LISP :IN SAVE-LISP-AND-DIE)) unhandled condition in --disable-debugger mode, quitting ┌─[phoe][phoetower][~] └─▪ echo $? 1