Warning: Cannot modify header information - headers already sent by (output started at index.php:1) in login_functions.inc.php on line 7
php 重定向出了问题，求大神帮助，我发誓已经找了6个小时了，还是没有找出哪里有问题
在我本地服务器上运行一切正常，但是一到网络上跑，就出现这个问题，我觉得，header前面只能出现错误信息，它前面确实没有任何输出了，那这个错误信息是什么呢？如何调试？我好郁闷。为什么本地服务器可以运行，一切正常，网络服务器就有这么多问题
回复讨论(解决方案)
打印$url校对，如果相同，再看看服务器上这几个引入的php有没有bom头
显然 index.php 有 BOM 头，而你的服务器的 php 版本较低
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