def get_file_content(file_name, offset, length):
    """ Read the content of a file given the offset and the length. The offset
    is where the read begins and length is how many characters will be read. If
    length is zero, it returns the entire line content """
    with open(file_name, "rb") as infile:
        infile.seek(offset, 0)
        if length == 0:
            return infile.readline().strip()
        return infile.read(length)