returns the socket family as an integer.
p Socket::Option.new(:INET6, :IPV6, :RECVPKTINFO, [1].pack("i!")).family #=> 10
Returns:
124 125 126 127 128
# File 'option.c', line 124 static VALUE sockopt_family_m(VALUE self) { return rb_attr_get(self, rb_intern("family")); }