简单地缓存任何PHP程序输出的思路

if  ( time ()  -   filemtime ( ' index.cache ' )  >   2   *   60 )     // 如果缓存文件为两分钟前更新，则重新生成缓存  
  @ob_start ( ' output ' );         // 使用output函数捕捉正常输出并缓存  
else                // 否则直接输出缓存页面  
{ 
   @ob_start ( ' ob_gzhandler ' ); 
   readfile ( ' index.cache ' ); 
   exit ; 
} 


function  output( $buffer ) 
{ 
   $scriptname   =   SERVER [ ' SCRIPT_FILENAME ' ];
if  ( $scriptname   ==   '' ) 
 $scriptname   =SERVER [ ' PATH_TRANSLATED ' ];
@ chdir ( dirname ( $scriptname ));
if  ( $fp   =  @ fopen ( ' index.cache ' ,   ' w ' ))
{
@ flock ( $fp ,  LOCK_EX);
@ fwrite ( $fp ,   $buffer );
@ fclose ( $fp );
}
if  ( function_exists ( ' gzencode ' )  &&     ereg ( ' gzip ' ,SERVER [ ' HTTP_ACCEPT_ENCODING ' ]))
{
header ( " Content-Encoding: gzip " );
return  @ gzencode ( $buffer ,   9 ,  FORCE_GZIP);
}
else
return   $buffer ;
}