I'd like to write compressed data to a file.
To improve performance, I want to use buffer.

I read some books, they all talk about 'character' stream.
But I think compressed data should be binary.

And, what buffer size if optimal?
How can I set the buffer size?

I need to checkpoint the buffer when
1) the buffer is full.
2) I have put all the data to the buffer.

Should I use standard library or boost?