+#ifdef CYGWIN
+DEFUN ("mswindows-cygwin-to-win32-path", Fmswindows_cygwin_to_win32_path, 1, 1, 0, /*
+Get the cygwin environment to convert the Unix PATH to win32 format.
+No expansion is performed, all conversion is done by the cygwin runtime.
+*/
+ (path))
+{
+ Extbyte* f;
+ Bufbyte* p;
+ CHECK_STRING (path);
+
+ /* There appears to be a bug in the cygwin conversion routines in
+ that they are not idempotent. */
+ p = XSTRING_DATA (path);
+ if (isalpha (p[0]) && (IS_DEVICE_SEP (p[1])))
+ return path;
+
+ /* Use mule and cygwin-safe APIs top get at file data. */
+ LOCAL_TO_WIN32_FILE_FORMAT (path, f);
+ return build_ext_string (f, Qnative);
+}
+#endif
+