+(define-designator filename c-string
+ (pathname (namestring (translate-logical-pathname filename)))
+ (string filename))
+
+(define-designator file-descriptor (integer 32)
+ (sb-impl::file-stream (sb-impl::fd-stream-fd file-descriptor))
+ (fixnum file-descriptor))
+
+(define-designator sap-or-nil sb-sys:system-area-pointer
+ (null (sb-sys:int-sap 0))
+ (sb-sys:system-area-pointer sap-or-nil))
+