Nginx+centos5.6 running PHP problem

My system is php+nginx+fastcgi+centos5.6

My site A for a two PHP

Http: / / www.xxxx.com / a.php

Content is as follows:

<?

Echo nginx PHP file_get_contents" test ( ) function";

? >

Http: / / www.xxxx.com / b.php

Content is as follows:

<?

echo file_get_contents (" http: / / www.xxxx.com / a.php." );

? >

Why I visit http: / / www.xxx.com / b.php page will timeout, does not display any content.

Http: / / www.xxxx.com / c.php content is as follows

<?

echo file_get_contents (" www.baidu.com" );

? >

It can display the contents of the www.baidu.com

What is nginx not prepared, or my CentOS server is not set