首先要说明：这个不是主页计数器，虽然原理和它相同。                               
一：准备一个计数文件，存放链结的url和访问次数，格式如下                          
id|url|count                                                                     
id是用来查找的索引号，url为实际文件的地址，count为次数                           
实例数据：                                                                       
doc01|docs/doc01.html|10                                                         
doc02|docs/doc02.html|10                                                         
二：准备count.php文件，代码如下：                                                
<?php                                                                            
//功能：传入参数id,在计数文件查找相应的url，增加计数，并返回实际的链接           
$countfile="count.txt";                                                          
$lines=file($countfile);//将计数文件内容读到数组$lines中                         
for($i=0;$i<count($lines);$i++)                                                  
{                                                                                
list($sid, $url, $count)=explode("|", $lines[$i]);                               
                                        //分解字符串为$id,$url,$count            
if($sid==$id) //查找指定id                                                       
{                                                                                
$count+=1; //增加计数                                                            
$lines[$i]=$sid . "|" . $url . "|" . "$count" . "\n";//重新生成计数字符串        
break;                                                                           

}                                                                                
}                                                                                
//写入计数信息                                                                   
$fp=fopen($countfile, "w");                                                      
for($i=0;$i<count($lines);$i++)                                                  
fputs($fp, $lines[$i]);                                                          
fclose($fp);                                                                     
Header("Location: $url");                                                        
?>                                                                               
注：这个是phpuser.com上的不完全版本，我加了一些改动，现在应该是能用的。          

三：主页中超链结的调用方式应该改为：                                             
<a href="count.php?id=doc01">doc01</a>                                           
程序功能是：                                                                     
首先将计数文件内容读到数组中                                                     
再从数组中查找指定id号，如找到则$url为相应的文件的真正链接，再将计数加1，        
重新生成计数信息                                                                 
将计数信息写入文件中                                                             
返回链接                                                                         

四：访问人数引用就是下面这几句，写个function也可以，我偷了把懒，                 
                      谁写好了给我一个  :)                                       
<?php                                                                            
$countfile="count.txt";                                                          
$lines=file($countfile);                                                         
list($sid,$url,$count) = explode("|",$lines[0]);//$lines[0]对应count.txt中       
                                                //第一条记录                     
echo $count;                                                                     
?>