silence missing prototype warning.

config.h.win32

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: config.h.win32,v 1.9 2004/04/10 04:03:16 marka Exp $ */
+/* $Id: config.h.win32,v 1.10 2004/04/19 05:52:21 marka Exp $ */
 
 /*
  * win32 configuration file
@@ -192,6 +192,7 @@ typedef long off_t;
 #define open	_open
 #define close	_close
 #define write	_write
+#include <io.h>
 #define isatty	_isatty
 
 #ifndef _WINSOCKAPI_