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pack

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Ói*¨: string pack(string format, mixed [args]...);

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A - SPACE- ×Ö*u´®ÌiÂu[padded string]

h ¨C Ê®Áu½øÖÆ×Ö*u´®£¬µÍ¡°ËÄλԪ¡±[low nibble first] (µÍλÔÚÇ°)

H - Ê®Áu½øÖÆ×Ö*u´®£¬¸ß¡°ËÄλԪ¡±high nibble first

c ¨C ´øÓÐuºÅµÄ×Öu

C ¨C ²»´øÓÐuºÅµÄ×Öu

s ¨C ´øÓÐ*uºÅµÄ¶Ìģʽ[short]£¨Í¨³£ÊÇ16룬°´»uÆ÷×Ö½Ú˳Ðo£(C)

S ¨C ²»´øÓÐ*uºÅµÄ¶Ìģʽ[short]£¨Í¨³£ÊÇ16룬°´»uÆ÷×Ö½ÚÅÅÐo£(C)

n -²»´øÓÐ*uºÅµÄ¶Ìģʽ[short]£¨Í¨³£ÊÇ16룬°´´oendian×Ö½ÚÅÅÐo£(C)

v -²»´øÓÐ*uºÅµÄ¶Ìģʽ[short]£¨Í¨³£ÊÇ16룬°´Ð¡endian×Ö½ÚÅÅÐo£(C)

i ¨C ´øÓÐ*uºÅµÄÕuÊý£¨ÓÉ´oСºÍ×Ö½Ú˳Ðo¾o¶¨£(C)

I ¨C ²»´øÓÐ*uºÅµÄÕuÊý£¨ÓÉ´oСºÍ×Ö½Ú˳Ðo¾o¶¨£(C)

l¨C ´øÓÐ*uºÅµÄ³¤Ä£Ê½[long]£¨Í¨³£ÊÇ32룬°´»uÆ÷×Ö½Ú˳Ðo£(C)

L ¨C ²»´øÓÐ*uºÅµÄ³¤Ä£Ê½[long]£¨Í¨³£ÊÇ32룬°´»uÆ÷×Ö½Ú˳Ðo£(C)

N ¨C ²»´øÓÐ*uºÅµÄ³¤Ä£Ê½[long]£¨Í¨³£ÊÇ32룬°´´oedian×Ö½Ú˳Ðo£(C)

V¨C ²»´øÓÐ*uºÅµÄ³¤Ä£Ê½[long]£¨Í¨³£ÊÇ32룬°´Ð¡edian×Ö½Ú˳Ðo£(C)

f ¨C¸¡µa£¨ÓÉ´oСºÍ×Ö½Ú˳Ðo¾o¶¨£(C)

d ¨C Ë«¾«¶È£¨ÓÉ´oСºÍ×Ö½Ú˳Ðo¾o¶¨£(C)

x ¨C ¿Õ×Ö½Ú[NUL byte]

X- ºoÃaeÒ»¸o×Ö½ÚBack up one byte

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Ói*¨: string pack(string format, mixed [args]...);

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    <?php 
    //´ae´¢ÕuÊý1234567890 
    file_put_contents("test.txt", 1234567890); 

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    <?php 
    print_r(unpack("i", file_get_contents("test.txt"))); 

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    <?php 
    file_put_contents("test.txt", "7-110-abcdefg-117"); 

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    <?php 
    file_put_contents("test.txt", pack("i2a7i1", 7, 110, "abcdefg", 117)); 

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    <?php 
    error_reporting(E_ALL); 

    class fileCacheException extends Exception{ 

    } 

    //Key-ValueÐÍÎļþ´ae´¢ 
    class fileCache{ 
       private $_file_header_size = 14; 
       private $_file_index_name; 
       private $_file_data_name; 
       private $_file_index;//Ë÷ÒýÎļþ¾a±u 
       private $_file_data;//Êý¾ÝÎļþ¾a±u 
       private $_node_struct;//Ë÷Òý½aµa½a¹¹Ìa 
       private $_inx_node_size = 36;//Ë÷Òý½aµa´oС 

       public function __construct($file_index="filecache_index.dat", $file_data="filecache_data.dat"){ 
         $this->_node_struct = array( 
            'next'=>array(1, 'V'), 
            'prev'=>array(1, 'V'), 
           'data_offset'=>array(1,'V'),//Êý¾Ý´ae´¢ÆðʼλÖà 
           'data_size'=>array(1,'V'),//Êý¾Ý³¤¶È 
           'ref_count'=>array(1,'V'),//ÒýÓô˴¦£¬Ä£*ÂPHPµÄÒýÓüÆÊýÏu»Ùģʽ 
           'key'=>array(16,'H*'),//´ae´¢KEY 
         ); 

         $this->_file_index_name = $file_index; 
         $this->_file_data_name = $file_data; 

         if(!file_exists($this->_file_index_name)){ 
            $this->_create_index(); 
         }else{ 
            $this->_file_index = fopen($this->_file_index_name, "rb+"); 
         } 

         if(!file_exists($this->_file_data_name)){ 
            $this->_create_data(); 
         }else{ 
            $this->_file_data = fopen($this->_file_data_name, "rb+");//¶þ½øÖÆ´ae´¢ÐeҪʹÓÃb 
         } 
       } 

       //´´½¨Ë÷ÒýÎļþ 
       private function _create_index(){ 
         $this->_file_index = fopen($this->_file_index_name, "wb+");//¶þ½øÖÆ´ae´¢ÐeҪʹÓÃb 
         if(!$this->_file_index)  
            throw new fileCacheException("Could't open index file:".$this->_file_index_name); 

         $this->_index_puts(0, '<'.'?php exit()?'.'>');//¶¨Î»ÎļþÁ÷ÖÁÆðʼλÖÃ0, *ÅÖÃphp±e¼Ç*ÀÖ¹ÏÂÔØ 
         $this->_index_puts($this->_file_header_size, pack("V1", 0)); 
       } 


       //´´½¨´ae´¢Îļþ 
       private function _create_data(){ 
         $this->_file_data = fopen($this->_file_data_name, "wb+");//¶þ½øÖÆ´ae´¢ÐeҪʹÓÃb 
         if(!$this->_file_index)  
            throw new fileCacheException("Could't open index file:".$this->_file_data_name); 

         $this->_data_puts(0, '<'.'?php exit()?'.'>');//¶¨Î»ÎļþÁ÷ÖÁÆðʼλÖÃ0, *ÅÖÃphp±e¼Ç*ÀÖ¹ÏÂÔØ 
       } 

       private function _index_puts($offset, $data, $length=false){ 
         fseek($this->_file_index, $offset); 

         if($length) 
         fputs($this->_file_index, $data, $length); 
         else 
         fputs($this->_file_index, $data); 
       } 

       private function _data_puts($offset, $data, $length=false){ 
         fseek($this->_file_data, $offset); 
         if($length) 
         fputs($this->_file_data, $data, $length); 
         else 
         fputs($this->_file_data, $data); 
       } 

       /** 
       * ÎļþËø 
       * @param $is_block ÊÇ*ñ¶ÀÕ¼¡¢×eÈuËø 
       */ 
       private function _lock($file_res, $is_block=true){ 
         flock($file_res, $is_block ? LOCK_EX : LOCK_EX|LOCK_NB); 
       } 

       private function _unlock($file_res){ 
         flock($file_res, LOCK_UN); 
       } 

       public function add($key, $value){ 
         $key = md5($key); 
         $value = serialize($value); 
         $this->_lock($this->_file_index, true); 
         $this->_lock($this->_file_data, true); 

         fseek($this->_file_index, $this->_file_header_size); 

         list(, $index_count) = unpack('V1', fread($this->_file_index, 4)); 

         $data_size = filesize($this->_file_data_name); 

         fseek($this->_file_data, $data_size); 

         $value_size = strlen($value); 

         $this->_data_puts(filesize($this->_file_data_name), $value); 

         $node_data =  
         pack("V1V1V1V1V1H32", ($index_count==0) ? 0 : $index_count*$this->_inx_node_size, 0, filesize($this->_file_data_name), strlen($value), 0, $key); 

         $index_count++; 

         $this->_index_puts($this->_file_header_size, $index_count, 4); 

         $this->_index_puts($this->get_new_node_pos($index_count), $node_data); 

         $this->_unlock($this->_file_data); 
         $this->_unlock($this->_file_index); 
       } 

       public function get_new_node_pos($index_count){ 
         return $this->_file_header_size + 4 + $this->_inx_node_size * ($index_count-1); 
       } 

       public function get_node($key){ 
         $key = md5($key); 
         fseek($this->_file_index, $this->_file_header_size); 
         $index_count = fread($this->_file_index, 4); 

         if($index_count>0) { 
            for ($i=0; $i < $index_count ; $i++) {  
              fseek($this->_file_index, $this->_file_header_size + 4 + $this->_inx_node_size * $i); 
              $data = fread($this->_file_index, $this->_inx_node_size); 
              $node = unpack("V1next/V1prev/V1data_offset/V1data_size/V1ref_count/H32key", $data); 

              if($key == $node['key']){ 
                 return $node; 
              } 
            } 
         }else{ 
            return null; 
         } 
       } 

       public function get_data($offset, $length){ 
         fseek($this->_file_data, $offset); 
         return unserialize(fread($this->_file_data, $length)); 
       } 
    } 

    //ʹÓÃ*½*¨ 
    $cache = new fileCache(); 
    $cache->add('abcdefg' , 'testabc'); 
    $data = $cache->get_node('abcdefg'); 
    print_r($data); 
    echo $cache->get_data($data['data_offset'], $data['data_size']); 

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    $LOGIN = array( 
       'COMMAND'=>array('a30', 'LOGIN'), 
       'DATA'=>array('a30', 'HELLO') 
    ); 

    $LOGOUT = array( 
       'COMMAND'=>array('a30', 'LOGOUT'), 
       'DATA'=>array('a30', 'GOOD BYE') 
    ); 

    $LOGIN_SUCCESS = array( 
       'COMMAND'=>array('a30', 'LOGIN_SUCCESS'), 
       'DATA'=>array('V1', 1) 
    ); 

    $LOGOUT_SUCCESS = array( 
       'COMMAND'=>array('a30', 'LOGIN_SUCCESS'), 
       'DATA'=>array('V1', time()) 
    ); 

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