unpacking network long that contain ints

[Joe Van Dyk]

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

 

[YANAGAWA Kazuhisa]

In Message-Id: <[email protected]>

# Works, but byte order is messed up
r, g, b = binary_data.unpack("CCCC")

irb(main):011:0> [0x123456].pack('N').unpack('C4').map {|e| '%x'%e}
=> ["0", "12", "34", "56"]

What do you mean by "messed up"? or do I missed something obvious?