Client/server fejl i cpp

Jeg har lige læst Grundlæggende Programmering i C++ (Globe), hvor forfatteren som eksempel laver flg. simple chatprogram.

Det er sammensat af flere includes, som jeg håber at jeg har samlet rigtigt.

Her er koden:

Server:
#include <winsock2.h>
#include <iostream>
using namespace std;
class Server
{

public:
    void StartServer(int port);
    void Luk();
private:
    int os,ns;
    sockaddr_in saddr;
    int clength, res, len;
    WSADATA wlib;
    char txt[100];
};


void Server::StartServer(int port)
{
    WSAStartup(0x0101, &wlib);
    saddr.sin_family = AF_INET;
    saddr.sin_port = htons(port);      // PORT NO.
    saddr.sin_addr.s_addr = INADDR_ANY;
    clength = sizeof(saddr);
    if((os = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))!=-1)
    {
        cout<<"Socket skabt"<<endl;
    }
    else
    {
        cout<<"Kunne ikke skabe socket"<<endl;
        Luk();
    }
    if((res = bind(os, (sockaddr *) &saddr, clength))!=-1)
    {
        cout<<"Bind OK"<<endl;
    }
    else
    {
        cout<<"Fejl i Bind(): Check portnumrene"<<endl;
        Luk();
    }
    if( (res = listen(os,5)) !=-1)
    { // backlog
        cout<<"Venter på en klient.."<<endl;
    }
    else
    {
        cout<<"Fejl i Listen"<<endl;
        Luk();
    }
    while(1)
    {
        ns = accept(os, (sockaddr *)&saddr, &clength);
        while((len = recv(ns, txt, sizeof(txt),0))!=0 )
        {
            cout <<"Data modtaget: " << txt<<endl;
        }
        closesocket(ns);
    }
    Luk();
}

void Server::Luk()
{
    closesocket(os);
    WSACleanup();
}

int main()
{
    Server s;
    s.StartServer(7777);
    return 0;
}

Client:

#include<iostream>
#include <winsock2.h>
using namespace std;


class Klient
{
public:
    void Connect(int port, char *adr);
    void SendMsg(char *pmsg);
    void CloseCon();
private:
    int fd;
    sockaddr_in saddr;
    WSADATA wlib;
    int nOk;
};


void Klient::Connect(int port, char *adr)
{
    WSAStartup(0x0101, &wlib);
    fd = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
    saddr.sin_family = AF_INET;
    saddr.sin_port = htons(port);
    saddr.sin_addr.s_addr = inet_addr(adr);
    connect(fd, (sockaddr *) &saddr, sizeof(saddr));
   
}

void Klient::SendMsg(char *pmsg)
{
    if( (nOk=send(fd, pmsg,100, 0)) == -1)
    {
        cout<<"Kunne ikke sende!"<<endl;
        exit(1);
    }
   
}

void Klient::CloseCon()
{
    closesocket(fd);
    WSACleanup();
}
char msg[100];
char stop;

int main()
{
    Klient k;
    k.Connect(7777,"127.0.0.1");
    do
    {
        cout<<"Send data til serveren:"<<endl;
        cin>>msg;
        k.SendMsg(msg);
        cout<<"Tast n for at stoppe"<<endl;
        cin>>stop;
    }
    while(stop!='n');
    k.CloseCon();
    return 0;
}
Ved kompileringen af begge filer siger den:
.objs\main.o:main.cpp:(.text+0x119): undefined reference to `WSAStartup@8'
.objs\main.o:main.cpp:(.text+0x13b): undefined reference to `socket@12'
.objs\main.o:main.cpp:(.text+0x15a): undefined reference to `htons@4'
.objs\main.o:main.cpp:(.text+0x16f): undefined reference to `inet_addr@4'
.objs\main.o:main.cpp:(.text+0x194): undefined reference to `connect@12'
.objs\main.o:main.cpp:(.text+0x1ca): undefined reference to `send@16'
.objs\main.o:main.cpp:(.text+0x227): undefined reference to `closesocket@4'
.objs\main.o:main.cpp:(.text+0x22f): undefined reference to `WSACleanup@0'

Fejlen er sikkert ret basal, noget med linker ell lign.

Jeg bruger Code::Blocks med GNU GCC comp.