(defvar buffer-file-numbers-unique (not (memq system-type '(windows-nt)))
"Non-nil means that buffer-file-number uniquely identifies files.")
+(defvar file-name-invalid-regexp
+ (cond ((and (eq system-type 'ms-dos) (not (msdos-long-file-names)))
+ (concat "\\(^\\([A-z]:\\)?/?.*:\\)\\|" ; colon except after drive
+ "[+, ;=|<>\"?*]\\|\\[\\|\\]\\|" ; invalid characters
+ "\\(/\\.\\.?[^/]\\)\\|" ; leading dots
+ "\\(/[^/.]+\\.[^/.]*\\.\\)")) ; more than a single dot
+ ((memq system-type '(ms-dos windows-nt))
+ (concat "\\(^\\([A-z]:\\)?/?.*:\\)\\|" ; colon except after drive
+ "[|<>\"?*]")) ; invalid characters
+ (t "[\000]"))
+ "Regexp recognizing file names which aren't allowed by the filesystem.")
+
(defcustom file-precious-flag nil
"*Non-nil means protect against I/O errors while saving files.
Some modes set this non-nil in particular buffers.