diff --git a/ikcp.c b/ikcp.c
index e92fcb4..3edb43f 100644
--- a/ikcp.c
+++ b/ikcp.c
@@ -292,6 +292,13 @@ ikcpcb* ikcp_create(IUINT32 conv, void *user)
 	return kcp;
 }
 
+//---------------------------------------------------------------------
+// set output function
+//---------------------------------------------------------------------
+void ikcp_setoutput(ikcpcb *kcp, int (*output)(const char *buf, int len, ikcpcb *kcp, void *user))
+{
+	kcp->output = output;
+}
 
 //---------------------------------------------------------------------
 // release a new kcpcb
diff --git a/ikcp.h b/ikcp.h
index 9167236..9b92b16 100644
--- a/ikcp.h
+++ b/ikcp.h
@@ -333,6 +333,9 @@ extern "C" {
 // output callback can be setup like this: 'kcp->output = my_udp_output'
 ikcpcb* ikcp_create(IUINT32 conv, void *user);
 
+// set output function
+void ikcp_setoutput(ikcpcb *kcp, int (*output)(const char *buf, int len, ikcpcb *kcp, void *user));
+
 // release kcp control object
 void ikcp_release(ikcpcb *kcp);