php对gzip的使用（实例）

代码如下:

if (!function_exists('gzdecode')) {
    function gzdecode ($data) {
        $flags = ord(substr($data, 3, 1));
        $headerlen = 10;
        $extralen = 0;
        $filenamelen = 0;
        if ($flags & 4) {
            $extralen = unpack('v' ,substr($data, 10, 2));
            $extralen = $extralen[1];
            $headerlen += 2 + $extralen;
        }
        if ($flags & 8) // Filename
            $headerlen = strpos($data, chr(0), $headerlen) + 1;
        if ($flags & 16) // Comment
            $headerlen = strpos($data, chr(0), $headerlen) + 1;
        if ($flags & 2) // CRC at end of file
            $headerlen += 2;
        $unpacked = @gzinflate(substr($data, $headerlen));
        if ($unpacked === FALSE)
              $unpacked = $data;
        return $unpacked;
     }
} 

调用简单：  

$f=@file_get_contents("http://www.jb51.net");
echo gzdecode($f);