diff --git a/src/io.c b/src/io.c
index aaa78c724..6bd4c3b60 100644
--- a/src/io.c
+++ b/src/io.c
@@ -49,7 +49,7 @@
             #define LWIP_PROVIDE_ERRNO 1
         #endif
     #elif defined(FREESCALE_MQX)
-        #include <errno.h>
+        #include <posix.h>
         #include <rtcs.h>
     #else
         #include <sys/types.h>