To what port number should be bind the server to ?

Can you provide some helper functions for Java as for C/C++?

Answer:

Python

def write_string_to_socket(connection, message): connection.send(message)

def read_string_from_socket(connection): return connection.recv(1024)

def process_client_connection(connection):

while True:
    # read message 
    message = read_string_from_socket(connection)

    print "Message received = ", message
    sys.stdout.flush()


    if message == "END":
        break
    write_string_to_socket(connection, message)

Simplely creating a write_string_to_socket call seems to pass the test without regard to multithreading in C++.

I'm pretty sure this isn't the answer they want, but I'm not sure what the correct answer would look like.

aww.. where is the .NET love? c# or f#? or even javascript would be nice

Bug: Python 3 shows nothing,

Yet Python 2 does provide sufficient hint to complete the answer.

"This challenge tests your understanding of Sockets and Multi-Threaded programming"

If you choose to use C, the only thing you have to do is add the logic to the function

void * process_client_connection(void * ptr)

which will be executed by the threads created when a connection is received. It doesn't really involve any Multi-Threaded programming since you never access variables that could be shared between threads. Or am I missing something?

Python: I had difficulty understanding what it wants me to do.

It simply wants you to define the methods read_string_from_socket, write_string_to_socket to call the appropriate methods on the socket. The socket is created, bound, etc for you and is passed to you as 'connection'.

The same thing (socket.send(), socket.recv(size)) works in Python 2 but not Python 3 - can someone tell me what has changed?

I'm doing this in C++14

I get following error on client

Traceback (most recent call last):
  File "/custom-lA6iT6IrH3LpFHyXDtxY/solution.py", line 66, in <module>
    readThread.start()
  File "/usr/lib/python2.7/threading.py", line 745, in start
    _start_new_thread(self.__bootstrap, ())
thread.error: can't start new thread

When I read string from socket in server I do not get any string. What I might be doing wrong? Could any of you who did in C/C++ share me your solution? Thanks.

Completed the challenge in c++.

It should be noted that all the messages from the clients have header - an unsigned int denoting the length (4byte) of each message and a tail - single char '/r' (0x13).

No multithreading is needed.