DELETE-DIRECTORY-AND-FILES (DIRNAME &KEY (IF-DOES-NOT-EXIST ERROR))
Recursively deletes all files and directories within the directory designated by the non-wild pathname designator DIRNAME including DIRNAME itself. IF-DOES-NOT-EXIST must be one of :ERROR or :IGNORE where :ERROR means that an error will be signaled if the directory DIRNAME does not exist. NOTE: this function is dangerous if the directory that you are removing contains symlinks to files outside of it - the target files might be removed instead! This is currently fixed for SBCL and CCL.
Checks whether the file named by the pathname designator PATHSPEC exists and if it is a directory. Returns its truename if this is the case, NIL otherwise. The truename is returned in directory form as if by PATHNAME-AS-DIRECTORY.