(PECL eio >= 0.0.1dev)
eio_readdir — Reads through a whole directory
   Reads through a whole directory(via the opendir, readdir and
   closedir system calls) and returns either the names or an array in
   result argument of callback
   function, depending on the flags argument.
  
pathDirectory path.
flagsCombination of EIO_READDIR_* constants.
pri请求的优先级:EIO_PRI_DEFAULT,EIO_PRI_MIN,EIO_PRI_MAX 或 null。如果是
null,pri 将设为
EIO_PRI_DEFAULT。
callback
callback
函数在请求完成时被调用。其应匹配一下原型:
void callback(mixed $data, int $result[, resource $req]);
data传递给请求的用户数据。
result针对请求的结果的值。通常是相应的系统调用返回的值。
req可选的请求资源,可被 eio_get_last_error() 之类的函数使用。
data
      Arbitrary variable passed to callback.
     
   eio_readdir() returns request resource on success, 或者在失败时返回 false. 
   Sets result argument of
   callback function according to
   flags:
  
EIO_READDIR_DENTS
      (int)
     'names' - array of directory names
       'dents' - array of struct
       eio_dirent-like arrays having the following keys each:
       'name' - the directory name;
       'type' - one of EIO_DT_*
       constants;
       'inode' - the inode number, if available, otherwise
       unspecified;
      
     EIO_READDIR_DIRS_FIRST
      (int)
     EIO_READDIR_STAT_ORDER
      (int)
     stat'ing each one. When planning to
      stat() all files in the given directory, the
      returned order will likely be
      fastest.
      
     EIO_READDIR_FOUND_UNKNOWN
      (int)
     Node types:
EIO_DT_UNKNOWN
      (int)
     EIO_DT_FIFO
      (int)
     EIO_DT_CHR
      (int)
     EIO_DT_MPC
      (int)
     EIO_DT_DIR
      (int)
     EIO_DT_NAM
      (int)
     EIO_DT_BLK
      (int)
     EIO_DT_MPB
      (int)
     EIO_DT_REG
      (int)
     EIO_DT_NWK
      (int)
     EIO_DT_CMP
      (int)
     EIO_DT_LNK
      (int)
     EIO_DT_SOCK
      (int)
     EIO_DT_DOOR
      (int)
     EIO_DT_WHT
      (int)
     EIO_DT_MAX
      (int)
     示例 #1 eio_readdir() example
<?php
/* Is called when eio_readdir() finishes */
function my_readdir_callback($data, $result) {
    echo __FUNCTION__, " called\n";
    echo "data: "; var_dump($data);
    echo "result: "; var_dump($result);
    echo "\n";
}
eio_readdir("/var/spool/news", EIO_READDIR_STAT_ORDER | EIO_READDIR_DIRS_FIRST,
  EIO_PRI_DEFAULT, "my_readdir_callback");
eio_event_loop();
?>
以上例程的输出类似于:
my_readdir_callback called
data: NULL
result: array(2) {
 ["names"]=>
  array(7) {
   [0]=>
    string(7) "archive"
    [1]=>
    string(8) "articles"
    [2]=>
    string(8) "incoming"
    [3]=>
    string(7) "innfeed"
    [4]=>
    string(8) "outgoing"
    [5]=>
    string(8) "overview"
    [6]=>
    string(3) "tmp"
  }
 ["dents"]=>
  array(7) {
   [0]=>
    array(3)
    {
     ["name"]=>
      string(7)
      "archive"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393265)
    }
   [1]=>
    array(3)
    {
     ["name"]=>
      string(8)
      "articles"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393266)
    }
   [2]=>
    array(3)
    {
     ["name"]=>
      string(8)
      "incoming"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393267)
    }
   [3]=>
    array(3)
    {
     ["name"]=>
      string(7)
      "innfeed"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393269)
    }
   [4]=>
    array(3)
    {
     ["name"]=>
      string(8)
      "outgoing"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393270)
    }
   [5]=>
    array(3)
    {
     ["name"]=>
      string(8)
      "overview"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393271)
    }
   [6]=>
    array(3)
    {
     ["name"]=>
      string(3)
      "tmp"
      ["type"]=>
      int(4)
      ["inode"]=>
      int(393272)
    }
  }
}