swoole执行错误

[ikingzo1]

php -m 显示已经有swoole，说明是安装成功了。所以想测试swoole的echo服务器。执行Server代码出现如下错误：
PHP Warning: Cannot convert to ordinal value in /root/swoole/swooleServer.php on line 15

Warning: Cannot convert to ordinal value in /root/swoole/swooleServer.php on line 15
PHP Warning: Cannot convert to ordinal value in /root/swoole/swooleServer.php on line 15

Warning: Cannot convert to ordinal value in /root/swoole/swooleServer.php on line 15
Segmentation fault