fixed bug #38219 Assert on TCP netconn_write with sndtimeout set

CHANGELOG

@@ -127,6 +127,9 @@ HISTORY
 
   ++ Bugfixes:
 
+  2014-10-21: Simon Goldschmidt
+  * api_msg.c: fixed bug #38219 Assert on TCP netconn_write with sndtimeout set
+
   2014-09-16: Kevin Cernekee
   * dns.c: patch #8480 Fix handling of dns_seqno wraparound
 

src/api/api_msg.c

@@ -1266,6 +1266,7 @@ lwip_netconn_do_writemore(struct netconn *conn)
       /* partial write */
       err = ERR_OK;
       conn->current_msg->msg.w.len = conn->write_offset;
+      conn->write_offset = 0;
     }
   } else
 #endif /* LWIP_SO_SNDTIMEO */