在研究一款商业程序的时候发现，其数据库没有任何授权加密，只是在首页有域名绑定的授权加密 首页明文为： <?php @Zend; 4147; /*
?This is not a text file!揄 */ print <<

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What is the Zend Optimizer?

The Zend Optimizer is one of the most popular PHP plugins for performance-improvement, and has been available without charge, since the early days of PHP 4. It improves performance by scanning PHP's intermediate code and passing it through multiple Optimization Passes to replace inefficient code patterns with more efficient code blocks. The replaced code blocks perform exactly the same operations as the original code, only faster.

In addition to improving performance, the Zend Optimizer also enables PHP to transparently load files encoded by the Zend Guard.

The Zend Optimizer is a free product available for download from Zend Technologies. Zend Technologies also developed the PHP scripting engine, known as the Zend Engine.