import socket
import sys

backlog = 1

clis = []
client = None

def do():
    # create a connection to the server which is actually accepted
    global client
    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    HOST = sys.argv[1]
    port = 4711
    print("connect", HOST, port)
    #client.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
    client.connect((HOST, port))


    # create as many connections as are kept by the backlog
    clis = []
    for i in range(backlog):
            print("cli", i)
            cli = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            #cli.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
            cli.connect((HOST, port))
            clis.append(cli)
    print("connections:", backlog, len(clis))

    print("creating cli2...")
    # create one more connection: this must fail
    cli2 = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #cli2.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
    cli2.settimeout(3)
    try:
        cli2.connect((HOST, port))
        assert False, "DAMMIT!"
    except socket.error:
        print("IT WORKS!!!!")

    print("sending server data (to exit)")
    client.send(b'x')
    client.close()
    print("client done")

try:
    do()
finally:
    print("closing pending connections")
    for cli in clis:
        cli.close()
    client.close()