Read a binary by blocks using regex

Hello to all in forum,

My first post here :), I hope somebody could help me out with my question.

I have a binary file from which I want to extract some patterns. The data is divided by blocks and
each block begins with 0xff 0x77.

Initially I would like to know how to print each block to be able to understand the basic and then how to
include regular expressions to extract some sequences from each block. My idea is to use ff77 as line separator
and read each block one by one in order to avoid overload buffer since the file is more than 2GB.

Maybe somebody could give an example code to begin.

Thanks in advance for any help.