src/w32proc.c (Fw32_get_codepage_charset): Doc fix. (Bug#19458)

src/ChangeLog

+2014-12-28  Eli Zaretskii  <eliz@gnu.org>
+
+	* w32proc.c (Fw32_get_codepage_charset): Doc fix.  (Bug#19458)
+
 2014-12-28  Paul Eggert  <eggert@Penguin.CS.UCLA.EDU>
 
 	Port memory-full checking to GnuTLS 3.3

src/w32proc.c

@@ -3054,7 +3054,12 @@ If successful, the new CP is returned, otherwise nil.  */)
 DEFUN ("w32-get-codepage-charset", Fw32_get_codepage_charset,
        Sw32_get_codepage_charset, 1, 1, 0,
        doc: /* Return charset ID corresponding to codepage CP.
-Returns nil if the codepage is not valid.  */)
+Returns nil if the codepage is not valid or its charset ID could
+not be determined.
+
+Note that this function is only guaranteed to work with ANSI
+codepages; most console codepages are not supported and will
+yield nil.  */)
   (Lisp_Object cp)
 {
   CHARSETINFO info;