circuitpython/tests/extmod/usocket_udp_nonblock.py

# test non-blocking UDP sockets

try:
    import usocket as socket, uerrno as errno
except ImportError:
    try:
        import socket, errno
    except ImportError:
        print("SKIP")
        raise SystemExit


s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.bind(socket.getaddrinfo("127.0.0.1", 8000)[0][-1])
s.settimeout(0)

try:
    s.recv(1)
except OSError as er:
    print("EAGAIN:", er.args[0] == errno.EAGAIN)