Scieneer Common Lisp 1.3.9 online documentation

ext:file-comment string[Macro]

When compile-file sees this form at top-level, it places the constant string in the run-time source location information. describe will print the file comment for the file that a function was defined in. The string is also textually present in the FASL, so the RCS "ident" command can find it, etc.