VS error C2064: term does not evaluate to a function taking 0 arguments

Hi everyone,
I finished following the winsock tutorial over at msdn and now I'm trying to adapt it in order to make an IRC server using multithreading. I git a couple errors when passing everything as params but I'm now stuck on this error :

 
Error	1	error C2064: term does not evaluate to a function taking 0 arguments

on line 58

Here is my code :
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#undef UNICODE

#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>
#include <iostream>
#include <thread>

// Need to link with Ws2_32.lib
#pragma comment (lib, "Ws2_32.lib")
// #pragma comment (lib, "Mswsock.lib")

//Global values
//I put them as global values in order to get the server up and running.
//I will try to pass them as params later on
int iResult;
struct addrinfo *result = NULL;
struct addrinfo hints;


//Prototypes
int listen(SOCKET ListenSocket);

#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "1016"

int main()
{
	std::cout << 1 << std::endl;
	WSADATA wsaData;

	SOCKET ListenSocket = INVALID_SOCKET;
	SOCKET ClientSocket = INVALID_SOCKET;

	int iSendResult;
	char recvbuf[DEFAULT_BUFLEN];
	int recvbuflen = DEFAULT_BUFLEN;

	// Initialize Winsock
	std::cout << 2 << std::endl;
	iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iResult != 0) {
		std::cout << 3 << std::endl;
		printf("WSAStartup failed with error: %d\n", iResult);
		return 1;
	}

	ZeroMemory(&hints, sizeof(hints));
	hints.ai_family = AF_INET;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_protocol = IPPROTO_TCP;
	hints.ai_flags = AI_PASSIVE;

	std::thread ListenThread{ listen(ListenSocket) };
	ListenThread.join();

	// Accept a client socket
	std::cout << 12 << std::endl;
	ClientSocket = accept(ListenSocket, NULL, NULL);
	if (ClientSocket == INVALID_SOCKET) {
		std::cout << 13 << std::endl;
		printf("accept failed with error: %d\n", WSAGetLastError());
		closesocket(ListenSocket);
		WSACleanup();
		return 1;
	}

	// No longer need server socket
	closesocket(ListenSocket);

	// Receive until the peer shuts down the connection
	do {
		std::cout << 14 << std::endl;
		iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);
		if (iResult > 0) {
			std::cout << 15 << std::endl;
			printf("Bytes received: %d\n", iResult);

			// Echo the buffer back to the sender
			std::cout << 16 << std::endl;
			iSendResult = send(ClientSocket, recvbuf, iResult, 0);
			if (iSendResult == SOCKET_ERROR) {
				std::cout << 17 << std::endl;
				printf("send failed with error: %d\n", WSAGetLastError());
				closesocket(ClientSocket);
				WSACleanup();
				return 1;
			}
			printf("Bytes sent: %d\n", iSendResult);
		}
		else if (iResult == 0) {
			std::cout << 18 << std::endl;
			printf("Connection closing...\n");
		}
		else {
			std::cout << 19 << std::endl;
			printf("recv failed with error: %d\n", WSAGetLastError());
			closesocket(ClientSocket);
			WSACleanup();
			return 1;
		}

	} while (iResult > 0);

	// shutdown the connection since we're done
	std::cout << 20 << std::endl;
	iResult = shutdown(ClientSocket, SD_SEND);
	if (iResult == SOCKET_ERROR) {
		std::cout << 21 << std::endl;
		printf("shutdown failed with error: %d\n", WSAGetLastError());
		closesocket(ClientSocket);
		WSACleanup();
		return 1;
	}

	std::cout << 22 << std::endl;
	// cleanup
	closesocket(ClientSocket);
	WSACleanup();

	return 0;
}

int listen(SOCKET ListenSocket)
{
	// Resolve the server address and port
	std::cout << 4 << std::endl;
	iResult = getaddrinfo(NULL, DEFAULT_PORT, &hints, &result);
	if (iResult != 0) {
		std::cout << 5 << std::endl;
		printf("getaddrinfo failed with error: %d\n", iResult);
		WSACleanup();
		return 1;
	}

	// Create a SOCKET for connecting to server
	std::cout << 6 << std::endl;
	ListenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
	if (ListenSocket == INVALID_SOCKET) {
		std::cout << 7 << std::endl;
		printf("socket failed with error: %ld\n", WSAGetLastError());
		freeaddrinfo(result);
		WSACleanup();
		return 1;
	}

	// Setup the TCP listening socket
	std::cout << 8 << std::endl;
	iResult = bind(ListenSocket, result->ai_addr, (int)result->ai_addrlen);
	if (iResult == SOCKET_ERROR) {
		std::cout << 9 << std::endl;
		printf("bind failed with error: %d\n", WSAGetLastError());
		freeaddrinfo(result);
		closesocket(ListenSocket);
		WSACleanup();
		return 1;
	}

	freeaddrinfo(result);

	std::cout << 10 << std::endl;
	iResult = listen(ListenSocket, SOMAXCONN);
	if (iResult == SOCKET_ERROR) {
		std::cout << 11 << std::endl;
		printf("listen failed with error: %d\n", WSAGetLastError());
		closesocket(ListenSocket);
		WSACleanup();
		return 1;
	}

}


I already googled it and went on the msdn page but that didn't help.
Any help is welcome,

mindoo
Argument to thread constructor is function taing no arguments. You are passing int to it (result of calling listen(istenSocket); — you call that function and then pass result to thread constructor).

You probably need to pass a lambda to thread:

std::thread ListenThread{ [ListenSocket](){listen(ListenSocket);} };
Thanks for your answer.
Whats a lambda ?
Ok, thanks for the links but I'm having a hard time understanding how I would use a lambda in my case.
Could you please tell me how to integrate a lambda in my proggramme ?
Thanks,

mindoo
I posted examle in first answer: std::thread ListenThread{ [ListenSocket](){listen(ListenSocket);} };
Sorry, I hadn't noticed I could actually use that in my code.
Thanks for your help,

mindoo
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