Page 209 - PDA Robotics Using Your Personal Digital Assistant to Control Your Robot

PDA 09 5/27/03 8:50 AM Page 185
Chapter 9 / PDA Robot Software for Pocket PC 2002
// to read the data by calling ioctlsocket. This will indicate how much data
// is in the buffer as well.
//
ret = ioctlsocket (Infrared_Socket, FIONREAD, &numbytes);
if( (ret == 0) && (numbytes > 0) )
{
//
// Receive what is in the buffer and set the
// range edit box
//
ret = recv ( Infrared_Socket, &irda_buffer[0], 26, 0);
this->m_range.SetWindowText( (LPCTSTR) CString(irda_buffer));
}
}
To close the IrDA link, press the Disconnect button and the following
function is called. It, in turn, calls CloseIrdaSocket listed below.

void CPDABotDlg::OnCloseIrda()
{
CloseIrdaSocket();
}

void CPDABotDlg::CloseIrdaSocket()
{

//
// Purge the receive buffer and close the Socket to disconnect.
//

char irda_buffer[128];
int ret;
u_long numbytes;

//
// Ensure that we won't be blocked waiting here on the function
// to read the data by calling ioctlsocket. This will indicate how much data
// is in the buffer as well.
//

ret = ioctlsocket (Infrared_Socket, FIONREAD, &numbytes);
if( (ret == 0) && (numbytes > 0) )
{
ret = recv ( Infrared_Socket, &irda_buffer[0], numbytes, 0);
}
ret = closesocket(Infrared_Socket);

//
// Set the member variable of this class that we use to determine our status
// of the link

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