Consider socket API on a Linux machine that supports connected UDP sockets. A connected UDP socket is a UDP socket on which connect function has already been called. Which of the following statements is/are CORRECT? I. A connected UDP socket can be used to communicate with multiple peers simultaneously. II. A process can successfully call connect function again for an already connected UDP socket.

In BSD/Linux socket programming with UDP (SOCK_DGRAM):

1. Statement I is incorrect: Calling connect() on a UDP socket associates the socket with a specific foreign IP address and port number. Once connected:

   • The socket will only receive datagrams arriving from that specific peer address.

   • Datagrams sent using write() or send() will automatically be transmitted to that specific peer.

   • Thus, a connected UDP socket cannot be used to communicate with multiple peers simultaneously.

2. Statement II is correct: Unlike TCP sockets (where connect() can only be called once to establish a 3-way handshake), a UDP socket can call connect() multiple times:

   • To reassign/reconnect to a new peer address and port.

   • To unconnect/dissociate the socket by setting the address family to AF_UNSPEC.

Therefore, only statement II is correct.

Hence, (B) is the correct option.