It seems walk-directory will skip files and directories whose name is in Unicode, such as Chinese.
(require "asdf")
(require "osicat")
(defpackage :com.losttemple.zip-db
(:use :common-lisp :osicat))
(in-package :com.losttemple.zip-db)
(walk-directory
(current-directory)
#'(lambda (x) (format t "~a~%" (absolute-pathname x)))
:test #'(lambda (x) (format t "---~a~%" (absolute-pathname x)) t)
:directories :depth-first)
(in-package :common-lisp-user)
(quit)
--
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Achilles Xu