From: Joe Van Dyk <joevandyk@...>
Date: 2005-04-02T11:20:57+09:00
Subject: unpacking network long that contain ints

Hi,

I have a binary file that contains a bunch of unsigned longs in
network byte order.  Each long contains 4 unsigned ints.

In C, I'd do:
           rgb_long = ntohl(rgb_long);

            /* Extract out the red, green, and blue elements from the 
             * RGB long. */
            red = rgb_long   << 0  >> 24;
            green = rgb_long << 8  >> 24;
            blue = rgb_long  << 16 >> 24;

In Ruby, I have:
                # I have the long in host byte order, but it's now a FixNum.
                rgb = binary_data.unpack("N")[0] 
              
                # Works, but byte order is messed up
                r, g, b = binary_data.unpack("CCCC") 

Ideas?

Thanks,
joe