PHP + MySql +存储过程,如何获取"out"值？

关于使用PHP的mysql中的存储过程,文档严重缺乏.我目前有一个通过PHP调用的存储过程,如何获取out参数的值？

它似乎在这篇文章中回答:

http://forums.mysql.com/read.php?52,198596,198717#msg-198717

使用mysqli PHP API:

假设sproc myproc(IN i int,OUT j int):

$mysqli = new mysqli(  "HOST", "USR", "PWD", "DBNAME" );
$ivalue=1;
$res = $mysqli->multi_query( "CALL myproc($ivalue,@x);SELECT @x" );
if( $res ) {
  $results = 0;
  do {
    if ($result = $mysqli->store_result()) {
      printf( "Result #%u:
", ++$results );
      while( $row = $result->fetch_row() ) {
        foreach( $row as $cell ) echo $cell, " ";
      }
      $result->close();
      if( $mysqli->more_results() ) echo "
";
    }
  } while( $mysqli->next_result() );
}
$mysqli->close();

这是一个如何使用mysql,mysqli和pdo执行此操作的示例:

http://www.joeyrivera.com/2009/using-mysql-stored-procedures-with-php-mysqlmysqlipdo/