Was missing, needed by "USB Port" print transport add-on.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@7651 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/drivers/USB_printer.h

@@ -0,0 +1,36 @@
+/* 
+** USB_printer.h
+**
+** Copyright 1999, Be Incorporated. All Rights Reserved.
+**
+*/
+
+#ifndef _USB_PRINTER_H
+#define _USB_PRINTER_H
+
+#include <Drivers.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* ioctl() opcodes for usb_printer driver */
+
+enum
+{
+	USB_PRINTER_GET_DEVICE_ID = B_DEVICE_OP_CODES_END+1
+};
+
+
+/* Maximum length of the DEVICE_ID. User MUST allocate this size
+when calling USB_PRINTER_GET_DEVICE_ID ioctl() */
+
+#define USB_PRINTER_DEVICE_ID_LENGTH	256
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif