What is BinData?

Do you ever find yourself writing code like this?

ruby io = File.open(...) len = io.read(2).unpack("v") name = io.read(len) width, height = io.read(8).unpack("VV") puts "Rectangle #{name} is #{width} x #{height}"

It’s ugly, violates DRY and feels like you’re writing Perl, not Ruby.

There is a better way. Here’s how you’d write the above using BinData.

```ruby class Rectangle < BinData::Record endian :little uint16 :len string :name, :read_length => :len uint32 :width uint32 :height end

io = File.open(…) r = Rectangle.read(io) puts “Rectangle #rr.name is #rr.width x #rr.height” ```

BinData makes it easy to create new data types. It supports all the common primitive datatypes that are found in structured binary data formats. Support for dependent and variable length fields is built in.


$ gem install bindata


$ sudo ruby setup.rb




$ rake manual


If you have any queries / bug reports / suggestions, please contact me (Dion Mendel) via email at dion@lostrealm.com