diff --git a/lib/lwip/src/include/lwip/api_msg.h b/lib/lwip/src/include/lwip/api_msg.h
new file mode 100644
index 0000000..3fef3dd
--- /dev/null
+++ b/lib/lwip/src/include/lwip/api_msg.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_API_MSG_H__
+#define __LWIP_API_MSG_H__
+
+#include "lwip/opt.h"
+#include "lwip/pbuf.h"
+#include "lwip/sys.h"
+
+#include "lwip/ip.h"
+
+#include "lwip/udp.h"
+#include "lwip/tcp.h"
+
+#include "lwip/api.h"
+
+enum api_msg_type {
+  API_MSG_NEWCONN,
+  API_MSG_DELCONN,
+  
+  API_MSG_BIND,
+  API_MSG_CONNECT,
+  API_MSG_DISCONNECT,
+
+  API_MSG_LISTEN,
+  API_MSG_ACCEPT,
+
+  API_MSG_SEND,
+  API_MSG_RECV,
+  API_MSG_WRITE,
+
+  API_MSG_CLOSE,
+  
+  API_MSG_MAX
+};
+
+struct api_msg_msg {
+  struct netconn *conn;
+  enum netconn_type conntype;
+  union {
+    struct pbuf *p;   
+    struct  {
+      struct ip_addr *ipaddr;
+      u16_t port;
+    } bc;
+    struct {
+      void *dataptr;
+      u16_t len;
+      u8_t copy;
+    } w;    
+    sys_mbox_t mbox;
+    u16_t len;
+  } msg;
+};
+
+struct api_msg {
+  enum api_msg_type type;
+  struct api_msg_msg msg;
+};
+
+void api_msg_input(struct api_msg *msg);
+void api_msg_post(struct api_msg *msg);
+
+#endif /* __LWIP_API_MSG_H__ */
+