diff --git a/HttpServer/Events/OnWorkerStart.php b/HttpServer/Events/OnWorkerStart.php
index 5c0f1e26..cd64822e 100644
--- a/HttpServer/Events/OnWorkerStart.php
+++ b/HttpServer/Events/OnWorkerStart.php
@@ -99,7 +99,9 @@ class OnWorkerStart extends Callback
     public function onSignal($server, $worker_id)
     {
         $env = ucfirst(Snowflake::getEnvironmental());
-        while (Coroutine::waitSignal($this->signal, -1)) {
+
+        $receive = Coroutine::waitSignal($this->signal, -1);
+        while ($receive === true) {
             if ($this->isPrint === false) {
                 $this->warning(sprintf('Receive %s#%d stop event.', $env, $worker_id));
                 $this->isPrint = true;