diff --git a/asminc/stdio.inc b/asminc/stdio.inc
new file mode 100644
index 000000000..fcf119b7e
--- /dev/null
+++ b/asminc/stdio.inc
@@ -0,0 +1,60 @@
+;*****************************************************************************/
+;*                                                                           */
+;*                                 stdio.inc                                 */
+;*                                                                           */
+;*                      Mirror definitions for stdio.h                       */
+;*                                                                           */
+;*                                                                           */
+;*                                                                           */
+;* (C) 2003      Ullrich von Bassewitz                                       */
+;*               Römerstrasse 52                                             */
+;*               D-70794 Filderstadt                                         */
+;* EMail:        uz@cc65.org                                                 */
+;*                                                                           */
+;*                                                                           */
+;* This software is provided 'as-is', without any expressed or implied       */
+;* warranty.  In no event will the authors be held liable for any damages    */
+;* arising from the use of this software.                                    */
+;*                                                                           */
+;* Permission is granted to anyone to use this software for any purpose,     */
+;* including commercial applications, and to alter it and redistribute it    */
+;* freely, subject to the following restrictions:                            */
+;*                                                                           */
+;* 1. The origin of this software must not be misrepresented; you must not   */
+;*    claim that you wrote the original software. If you use this software   */
+;*    in a product, an acknowledgment in the product documentation would be  */
+;*    appreciated but is not required.                                       */
+;* 2. Altered source versions must be plainly marked as such, and must not   */
+;*    be misrepresented as being the original software.                      */
+;* 3. This notice may not be removed or altered from any source              */
+;*    distribution.                                                          */
+;*                                                                           */
+;*****************************************************************************/
+
+
+
+;----------------------------------------------------------------------------
+; Constants
+
+_IOFBF		= 0
+_IOLBF		= 1
+_IONBF		= 2
+BUFSIZ		= 256
+EOF 	      	= -1
+FILENAME_MAX	= 16
+FOPEN_MAX	= 8
+L_tmpnam	= (FILENAME_MAX + 1)
+SEEK_CUR	= 0
+SEEK_END	= 1
+SEEK_SET	= 2
+TMP_MAX		= 256
+
+;----------------------------------------------------------------------------
+; External variables
+
+        .global _stdin
+        .global _stdout
+        .global _stderr
+
+
+