How to disconnect UDP sockets in Python _python

A UDP socket can be connected to a specified address using the Connect system call. Since then, this socket will only receive data from this address, and you can use the Send system call to send data directly without specifying an address. You can call connect again to connect to another place. But in Python, once you call connect, you're no longer able to return to the initial state of receiving data from any address!

This is the Python API limit, and there's no way to pass the Connect method to the Af_unspec address cluster (written in C code). C inside can do (code from here):

Copy Code code as follows:

int disconnect_udp_sock (int fd) {
struct sockaddr_in sin;

memset ((char *) &sin, 0, sizeof (sin));
sin.sin_family = Af_unspec;
Return (Connect (FD, (struct sockaddr *) &sin, sizeof (sin));
}

But since it's a Python limitation, take ctypes and get around, there's some trouble:

Copy Code code as follows:

From ctypes import Cdll, Create_string_buffer

def disconnect (sock):
libc = Cdll ("libc.so.6")
BUF = Create_string_buffer (a) # sizeof struct SOCKADDR_IN
Libc.connect (Sock.fileno (), buf, 16)

The value of the Af_unspec is 0, so it is possible to pass a full 0 buffer as long as struct sockaddr_in to connect.:-)