phpshmop_open的有关问题

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<!--?php
$arr=array();
function application($key,$value="")
{
    global $arr;
    if($value=="")
    {
        $shm_id = @shmop_open(12345, "a", 0644,100);
    }else{
        @$shm_id = shmop_open(12345, "c",0,0);
        if(!$shm_id)
        {
            $shm_id=shmop_open(12345,"c",0644,100);
        }
    }
    @$byte=shmop_read($shm_id,0,1024*1024);
    if(!$byte){
        return "";
    }else{
        if($byte!=""){
            $arr=unserialize($byte);
        }else{
            return "";
        }
    }
    if($value=="")//取值
    {
        shmop_close($shm_id);
        if(array_key_exists($key,$arr))
        {
            return $arr[$key];
        }
        return "";
    }else{
        $arr[$key]=$value;
        shmop_write($shm_id,serialize($arr),0);
        shmop_close($shm_id);
    }
}
?-->

$p = new shared;
//$p->a = 'abcd';
//$p->b = 1234;
print_r($p->_all);
echo $p->b;
class shared {
  private $shm_id;
  private $shm_key = 0xff3;
  private $shm_size = 1024;
  function __construct() {
    $this->shm_id = shmop_open($this->shm_key, "c", 0644, $this->shm_size) or die('申请失败');
  }
  function __get($name) {
    $buf = shmop_read($this->shm_id, 0, $this->shm_size);
    $buf = unserialize(trim($buf));
    if($name == '_all') return $buf;
    return isset($buf[$name]) ? $buf[$name] : false;
  }
  function __set($name, $value) {
    $buf = shmop_read($this->shm_id, 0, $this->shm_size);
    $buf = unserialize(trim($buf));
    $buf[$name] = $value;
    $buf = serialize($buf);
    if(strlen($buf) >= $this->shm_size) die('空间不足');
    shmop_write($this->shm_id, $buf, 0) or die('写入失败');
  }
}
<br><font color="#e78608">------解决方案--------------------</font><br>和你上一个帖子一样，讨论是在基于 php_shmop.dll 扩展的<br><br>linux 中有另外的方法，但原理是一样的<br>php_shmop 也可以在 linux 中编译，但他却是为 window 设计的<br>
<br><font color="#e78608">------解决方案--------------------</font><br>我就明着告诉你,你这个问题大了.<br><br>共享内存区需要加锁操作, php没法设置进程共享的mutex, 你可以同样适用一个system v 的sem二值信号量来做锁.