extern "c" fn recvfrom(c.T, *anyopaque, usize, u32, ?*c.T, ?*c.T) callconv(.C) if (builtin.os.tag == .windows) c_int else isize
sockfd: c.T,
buf: *anyopaque,
len: usize,
flags: u32,
src_addr: ?*c.T,
addrlen: ?*c.T,