Referenced structure not 'sticking' [closed]

// ...
    CCommsProperties props;

    pController->GetProperties( props );
    if (props.handshake != HANDSHAKE_RTS_CTS)
    {
    	props.handshake = HANDSHAKE_RTS_CTS;
    	pController->RefreshCommProperties( props );
    }

// ... in another file:
void CControllerSI::RefreshCommProperties ( const CCommsProperties& props )
{
    // ... code ...
}