在Ruby中编写二进制文件

Question

Is there a simple way to write binary data into binary file like we used to do in C/C++? For example, how can I create a 4-byte file with serialized 4-byte integer value without using fancy math?

Answer 1

You can use Array#pack and String#unpack to convert to and from binary representations. Combine them with IO#write and IO#read , and away you go.

Answer 2

I recently had a similar problem for work. I used the BinData gem and it worked a treat. You just do something like:

File.open('test.bin', 'wb') {|file| BinData::Int32be.new(12345).write(file) }

and you don't need to remember any Array#pack codes.

Answer 3

There are Marshal.dump and Marshal.load methods you can use.

Here's a link: http://en.wikipedia.org/wiki/Serialization#Ruby .

And another that saves the data to a file: http://rubylearning.com/satishtalim/object_serialization.html .

Answer 4

In my humble oppinion, ruby wasn't made for such tasks. If you have to write to binary files a lot, it would be easiest to write some c functions for that and call them from ruby, which is quite easy using swig. I'm doing the same thing at the moment to write a raid simulator.