I was doing M-! (shell-command) of: mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C and xemacs with a failed assertion. It did not execute the mv command before the crash. I'm on redhat6.0. I am not able to reproduce the crash. - Cotton Fatal error: assertion failed, file lisp.h, line 969, RECORD_TYPEP (obj, &lrecord_string) Fatal error (6). Your files have been auto-saved. Use `M-x recover-session' to recover them. If you have access to the PROBLEMS file that came with your version of XEmacs, please check to see if your crash is described there, as there may be a workaround available. Otherwise, please report this bug by running the send-pr script included with XEmacs, or selecting `Send Bug Report' from the help menu. As a last resort send ordinary email to `crashes(a)xemacs.org&#39;. *MAKE SURE* to include the information in the command M-x describe-installation. If at all possible, *please* try to obtain a C stack backtrace; it will help us immensely in determining what went wrong. To do this, locate the core file that was produced as a result of this crash (it's usually called `core' and is located in the directory in which you started the editor, or maybe in your home directory), and type gdb /usr/xemacs-21.2.23/bin/xemacs core then type `where' when the debugger prompt comes up. (If you don't have GDB on your system, you might have DBX, or XDB, or SDB. A similar procedure should work for all of these. Ask your system administrator if you need more help.) Lisp backtrace follows: call-process-internal("/bin/bash" "/tmp/emacsNzCT3M" #<buffer "*Shell Command Output*"> nil "-c" "mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C") apply(call-process-internal "/bin/bash" "/tmp/emacsNzCT3M" #<buffer "*Shell Command Output*"> nil ("-c" "mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C")) # bind (args displayp buffer infile program) call-process("/bin/bash" "/tmp/emacsNzCT3M" #<buffer "*Shell Command Output*"> nil "-c" "mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C") apply(call-process "/bin/bash" "/tmp/emacsNzCT3M" #<buffer "*Shell Command Output*"> nil ("-c" "mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C")) # (unwind-protect ...) # bind (temp args displayp buffer deletep program end start) call-process-region(956 956 "/bin/bash" nil #<buffer "*Shell Command Output*"> nil "-c" "mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C") # (unwind-protect ...) # bind (buffer success exit-status directory replace output-buffer command end start) shell-command-on-region(956 956 "mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C" nil) # (unwind-protect ...) # bind (match-data output-buffer command) #<compiled-function (command &optional output-buffer) "...(66)" [output-buffer bufferp barf-if-buffer-read-only push-mark call-process shell-file-name nil t shell-command-switch command exchange-point-and-mark match-data match-data (...) string-match "[ ]*&[ ]*$" background 0 shell-command-on-region] 7 699164 (list (read-shell-command "Shell command: ") current-prefix-arg)>("mv Tiger_FragmentTemplateMatch_RuleSet.C Tiger_FragmentMatch_RuleSet.C" nil) call-interactively(shell-command) # (condition-case ... . error) # (catch top-level ...)