diff --git a/c/lua/_demo/coroutine-cfunc/coroutine.go b/c/lua/_demo/coroutine-cfunc/coroutine.go
new file mode 100644
index 00000000..676a5bfc
--- /dev/null
+++ b/c/lua/_demo/coroutine-cfunc/coroutine.go
@@ -0,0 +1,42 @@
+package main
+
+import (
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/c/lua"
+)
+
+func coroutineFunc(L *lua.State) c.Int {
+	c.Printf(c.Str("Coroutine started\n"))
+	L.Yield(0) // Pause the coroutine
+	c.Printf(c.Str("Coroutine resumed\n"))
+	return 0
+}
+
+func main() {
+	L := lua.Newstate()
+	defer L.Close()
+
+	L.Openlibs()
+	co := L.Newthread()
+	L.Pushcfunction(coroutineFunc)
+	L.Xmove(co, 1)
+
+	var nres c.Int
+
+	c.Printf(c.Str("Resuming coroutine for the first time\n"))
+	result := co.Resume(nil, 0, &nres)
+	if result == lua.YIELD {
+		c.Printf(c.Str("Coroutine yielded\n"))
+		result = co.Resume(nil, 0, &nres)
+		if result == 0 {
+			c.Printf(c.Str("Coroutine finished\n"))
+		}
+	}
+}
+
+/* Expected output:
+Resuming coroutine for the first time
+Coroutine started
+Coroutine yielded
+Coroutine finished
+*/
diff --git a/c/lua/_demo/coroutine/coroutine.go b/c/lua/_demo/coroutine/coroutine.go
index feee0f66..ed05d98b 100644
--- a/c/lua/_demo/coroutine/coroutine.go
+++ b/c/lua/_demo/coroutine/coroutine.go
@@ -36,8 +36,8 @@ func main() {
 	// Resume coroutine and handle yields
 	for {
 		status = co.Resume(nil, 0, &nres)
-		c.Printf(c.Str("Resuming coroutine %d...\n"), status)
 		if status == lua.YIELD {
+			c.Printf(c.Str("Resuming coroutine %d...\n"), status)
 			yieldValue := co.Tointeger(-1)
 			c.Printf(c.Str("Yield value: %d\n"), yieldValue)
 			co.Pop(1) // Clean up the stack
@@ -58,3 +58,23 @@ func main() {
 	finalStatus := co.Status()
 	c.Printf(c.Str("Final status of coroutine: %d\n"), finalStatus)
 }
+
+/* Expected output:
+Resuming coroutine...
+Resuming coroutine 1...
+Yield value: 1
+Coroutine is yieldable.
+Resuming coroutine 1...
+Yield value: 2
+Coroutine is yieldable.
+Resuming coroutine 1...
+Yield value: 3
+Coroutine is yieldable.
+Resuming coroutine 1...
+Yield value: 4
+Coroutine is yieldable.
+Resuming coroutine 1...
+Yield value: 5
+Coroutine is yieldable.
+Final status of coroutine: 0
+*/
diff --git a/c/lua/lua.go b/c/lua/lua.go
index 0dad8493..86f3a532 100644
--- a/c/lua/lua.go
+++ b/c/lua/lua.go
@@ -146,7 +146,6 @@ type KFunction func(L *State, status c.Int, ctx KContext) c.Int
 func (L *State) Close() {}
 
 // State *(lua_newstate) (lua_Alloc f, void *ud);
-// State *(lua_newthread) (State *L);
 
 // llgo:link (*State).Newthread C.lua_newthread
 func (L *State) Newthread() *State { return nil }
@@ -353,9 +352,9 @@ func (L *State) Status() c.Int { return 0 }
 // llgo:link (*State).Isyieldable C.lua_isyieldable
 func (L *State) Isyieldable() c.Int { return 0 }
 
-// TODO(zzy)
-// int  (lua_yieldk)     (State *L, int nresults, lua_KContext ctx, lua_KFunction k);
-// #define lua_yield(L,n)	lua_yieldk(L, (n), 0, NULL)
+// llgo:link (*State).Yieldk C.lua_yieldk
+func (L *State) Yieldk(nresults c.Int, ctx KContext, k KFunction) c.Int { return 0 }
+func (L *State) Yield(nresults c.Int) c.Int                             { return L.Yieldk(nresults, nil, nil) }
 
 // /*
 // ** Warning-related functions