Tapi

You can download an example code from Microsoft web site:
http://www.microsoft.com/WIN32DEV/NETWRK/CTA2669B.ZIP
The example creates the CTapiConnection class. It provides an easy way to initialize TAPI, connect, and make a voice-based telephone call.

First of all I should have mentioned that I'm using Borland c++ 5 and not visual C (the example was for visual c)
Second, is is an example to make a call.  I still don't know haw to receive a call or recognise the button the caller pressed.

Edited text of question

Adjusted points to 80

Why isn't mthis working :
...
lReturn = lineInitialize(&hLineApp, hInstance, lineCallbackFunc,
      szAppName, &dwNumDevs)
...
lReturn = lineOpen(hLineApp, 0,&hLine, dwApiVersion, 0,0,LINECALLPRIVILEGE_MONITOR,0,0);
...
void CALLBACK lineCallbackFunc(
    DWORD dwDevice, DWORD dwMsg, DWORD dwCallbackInstance,
    DWORD dwParam1, DWORD dwParam2, DWORD dwParam3)
{
      cout << "A message is received !";
... }

And how can I make my program wait for a call ? If it does nothing it just closes !

This is how I do it.
Works with BC4.53 and BC5.01.

bool TTapi::Start( LPCSTR appName )
{
.
. Declare variables
.
      if ( ( _lpfnLineCallback = (LINECALLBACK) MakeProcInstance( (FARPROC) lineCallbackFunc, hInst() ) ) == NULL )
            {
            return( false );
            }
      lRet = lineInitialize( &_hLineApp, hInst(), _lpfnLineCallback, appName, _dwNumDevs );
      if ( lRet < 0 )
            {
            return( false );
            }
      lineRegisterRequestRecipient( hLineApp(), (DWORD)this, LINEREQUESTMODE_MAKECALL, true );
      // fill lineCapsList with LineCaps object
      for ( dwDeviceId = 0; dwDeviceId < _dwNumDevs; dwDeviceId++ )
            {
            TRACE("LineDevice = " << dwDeviceId );
            LONG lRet;
            HLINE hLine;
            DWORD dwEXTVersion = 0;
            LINEEXTENSIONID extensionID;
            bool mdExt, claraExt, maryExt;
            TRACE("lineNegotiateAPIVersion");
            lRet = lineNegotiateAPIVersion( _hLineApp, dwDeviceId, SupportAPILowVersion(), SupportAPIHighVersion(), _dwAPIVersion, &extensionID );
            if ( lRet < 0 )
                  {
                  return( false );
                  }
            mdExt                  = isMD110Ext(      extensionID );
            claraExt      = isClaraExt(      extensionID );
            maryExt            = isMaryExt(      extensionID );
            if ( mdExt || claraExt || maryExt )
                  {
                  lRet = lineNegotiateExtVersion( _hLineApp, dwDeviceId, _dwAPIVersion, SupportExtLowVersion(), SupportExtHighVersion(), &dwEXTVersion );
                  if ( lRet < 0 )
                        {
                        dwEXTVersion = 0;
                        return( false );
                        }
                  }
            else
                  {
                  dwEXTVersion = 0;
                  }
            if ( mdExt || claraExt )
                  {
                  lRet = lineOpen( _hLineApp, dwDeviceId, (LPHLINE) &hLine, _dwAPIVersion, dwEXTVersion, (DWORD) this, LINECALLPRIVILEGE_MONITOR | LINECALLPRIVILEGE_OWNER, LINEMEDIAMODE_INTERACTIVEVOICE, 0 );
                  }
            else
                  {
                  lRet = lineOpen( _hLineApp, dwDeviceId, (LPHLINE) &hLine, _dwAPIVersion, 0, (DWORD) this, LINECALLPRIVILEGE_MONITOR | LINECALLPRIVILEGE_OWNER, LINEMEDIAMODE_INTERACTIVEVOICE, 0 );
                  if ( lRet < 0 )
                        {
                        TRACE("First lineOpen failed with error = " << lRet );
                        // Unimodem can not open line with owner priviliege
                        lRet = lineOpen( _hLineApp, dwDeviceId, (LPHLINE) &hLine, _dwAPIVersion, 0, (DWORD) this, LINECALLPRIVILEGE_MONITOR, LINEMEDIAMODE_INTERACTIVEVOICE, 0 );
                        }
                  if ( lRet < 0 )
                        {
                        TRACE( "Second lineOpen failed with error = " << lRet );
                        continue;                        // just skip this line device, it's not voice
                        }
                  }
            if ( lRet < 0 )
                  {
                  return( false );
                  }
            // fill lineList with LineDev object
            LineDevice::LineTypeEnum lineType = mdExt ? LineDevice::ltMD110 : claraExt ? LineDevice::ltClaraBGS : maryExt ? LineDevice::ltMary :LineDevice::ltUnknown;
            LineDevice * pLineDevice;
            if ( lineType == LineDevice::ltMary )
                  {
                  pLineDevice = new LineDeviceMary( hLine, dwDeviceId, _dwAPIVersion, dwEXTVersion, extensionID, lineType );
                  }
            pLineDevice = new LineDevice( hLine, dwDeviceId, _dwAPIVersion, dwEXTVersion, extensionID, lineType );
            // get line device capabilities
            LineCaps lineCaps( _hLineApp, pLineDevice );
            lineCaps.capability();
            if ( mdExt || claraExt )
                  {
                  SwitchInfo( lineCaps.switchInfo() );
                  getMsgDivTextStrings( lineCaps );
                  }
            pLineDevice->SetLineName( lineCaps.lineName() );
            pLineDevice->SetPPId( lineCaps.PPId() );
            lineList().AddAtTail( pLineDevice );
            if ( pLineDevice->GetLineType() == LineDevice::ltMD110 )
                  {
                  LineDevice::SetMD110Line( pLineDevice );
                  StrStream str;
                  IniFile ini( IniFileTelephone );
                  DWORD dw = lineCaps.PPId() >> 16;
                  str << "Provider" << dw << ends;
                  setDefaultTimeout( ini.read( str.str(), EntryTimeoutASYNC, (unsigned int) 5000 ) );
                  }
            if ( pLineDevice->GetLineType() == LineDevice::ltClaraBGS )
                  {
                  LineDevice::SetClaraLine( pLineDevice );
                  }
            TRACE("Before if ( !FillAddresses( pLineDevice, &lineCaps ) )");
            if ( !FillAddresses( pLineDevice, &lineCaps ) )
                  {
                  return( false );
                  }
            lineSetStatusMessages(      hLine,
                                                                                    LINEDEVSTATE_OTHER |
                                                                                    LINEDEVSTATE_RINGING |
                                                                                    LINEDEVSTATE_CONNECTED |
                                                                                    LINEDEVSTATE_DISCONNECTED |
                                                                                    LINEDEVSTATE_MSGWAITON |
                                                                                    LINEDEVSTATE_MSGWAITOFF |
                                                                                    LINEDEVSTATE_INSERVICE |
                                                                                    LINEDEVSTATE_OUTOFSERVICE |
                                                                                    LINEDEVSTATE_MAINTENANCE |
                                                                                    LINEDEVSTATE_OPEN |
                                                                                    LINEDEVSTATE_CLOSE |
                                                                                    LINEDEVSTATE_NUMCALLS |
                                                                                    LINEDEVSTATE_NUMCOMPLETIONS |
                                                                                    LINEDEVSTATE_TERMINALS |
                                                                                    LINEDEVSTATE_ROAMMODE |
                                                                                    LINEDEVSTATE_BATTERY |
                                                                                    LINEDEVSTATE_SIGNAL |
                                                                                    LINEDEVSTATE_DEVSPECIFIC |
                                                                                    LINEDEVSTATE_REINIT |
                                                                                    LINEDEVSTATE_LOCK,
                                                                                    LINEADDRESSSTATE_OTHER |
                                                                                    LINEADDRESSSTATE_DEVSPECIFIC |
                                                                                    LINEADDRESSSTATE_INUSEZERO |
                                                                                    LINEADDRESSSTATE_INUSEONE |
                                                                                    LINEADDRESSSTATE_INUSEMANY |
                                                                                    LINEADDRESSSTATE_NUMCALLS |
                                                                                    LINEADDRESSSTATE_FORWARD |
                                                                                    LINEADDRESSSTATE_TERMINALS );
            checkLineStatus( pLineDevice );
            }
      _killTimer = new KillOCTimer( this, 500 );
      return true;
}