$NetBSD: patch-ad,v 1.1 2003/09/09 14:52:56 jmmv Exp $

--- libplot/z_write.c.orig	2000-06-20 13:34:42.000000000 +0900
+++ libplot/z_write.c	2003-09-09 21:22:59.000000000 +0900
@@ -484,7 +484,7 @@
   ostream *stream;
 
   stream = (ostream *)png_get_io_ptr (png_ptr);
-  stream->write (data, length);
+  stream->write ((const char *)data, length);
 }
 
 static void