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copied!<p>I decided to punt on this and to do away with the dependency on the SetupDi() functions. Instead, I have written code that traverses the subkeys in HKEY_LOCAL_MACHINE\System\CurrentControlSet\Enum to find any drivers that support the serial port GUID. I have the feeling that this is what the device manager does. In case anyone is interested, my code fragment can be seen below:</p> <pre><code>typedef std::string StrAsc; typedef std::pair<StrAsc, StrAsc> port_name_type; typedef std::list<port_name_type> friendly_names_type; void SerialPortBase::list_ports_friendly(friendly_names_type &port_names) { // we will first get the list of names. This will ensure that, at the very least, we get // the same list of names as we would have otherwise obtained. port_names_type simple_list; list_ports(simple_list); port_names.clear(); for(port_names_type::iterator pi = simple_list.begin(); pi != simple_list.end(); ++pi) port_names.push_back(friendly_name_type(*pi, *pi)); // we will now need to enumerate the subkeys of the Enum registry key. We will need to // consider many levels of the registry key structure in doing this so we will use a list // of key handles as a stack. HKEY enum_key ; char const enum_key_name[] = "SYSTEM\\CurrentControlSet\\Enum"; StrAsc const com_port_guid("{4d36e978-e325-11ce-bfc1-08002be10318}"); char const class_guid_name[] = "ClassGUID"; char const friendly_name_name[] = "FriendlyName"; char const device_parameters_name[] = "Device Parameters"; char const port_name_name[] = "PortName"; long rcd = ::RegOpenKeyEx( HKEY_LOCAL_MACHINE, enum_key_name, 0, KEY_READ, &enum_key); char value_buff[MAX_PATH]; StrAsc port_name, friendly_name; if(!port_names.empty() && rcd == ERROR_SUCCESS) { std::list<HKEY> key_stack; key_stack.push_back(enum_key); while(!key_stack.empty()) { // we need to determine whether this key has a "ClassGUID" value HKEY current = key_stack.front(); uint4 value_buff_len = sizeof(value_buff); key_stack.pop_front(); rcd = ::RegQueryValueEx( current, class_guid_name, 0, 0, reinterpret_cast<byte *>(value_buff), &value_buff_len); if(rcd == ERROR_SUCCESS) { // we will only consider devices that match the com port GUID if(com_port_guid == value_buff) { // this key appears to identify a com port. We will need to get the friendly name // and try to get the 'PortName' from the 'Device Parameters' subkey. Once we // have those things, we can update the friendly name in our original list value_buff_len = sizeof(value_buff); rcd = ::RegQueryValueEx( current, friendly_name_name, 0, 0, reinterpret_cast<byte *>(value_buff), &value_buff_len); if(rcd == ERROR_SUCCESS) { HKEY device_parameters_key; rcd = ::RegOpenKeyEx( current, device_parameters_name, 0, KEY_READ, &device_parameters_key); if(rcd == ERROR_SUCCESS) { friendly_name = value_buff; value_buff_len = sizeof(value_buff); rcd = ::RegQueryValueEx( device_parameters_key, port_name_name, 0, 0, reinterpret_cast<byte *>(value_buff), &value_buff_len); if(rcd == ERROR_SUCCESS) { friendly_names_type::iterator fi; port_name = value_buff; fi = std::find_if( port_names.begin(), port_names.end(), port_has_name(port_name)); if(fi != port_names.end()) fi->second = friendly_name; } ::RegCloseKey(device_parameters_key); } } } } else { // since this key did not have what we expected, we will need to check its // children uint4 index = 0; rcd = ERROR_SUCCESS; while(rcd == ERROR_SUCCESS) { value_buff_len = sizeof(value_buff); rcd = ::RegEnumKeyEx( current, index, value_buff, &value_buff_len, 0, 0, 0, 0); if(rcd == ERROR_SUCCESS) { HKEY child; rcd = ::RegOpenKeyEx(current, value_buff, 0, KEY_READ, &child); if(rcd == ERROR_SUCCESS) key_stack.push_back(child); } ++index; } } ::RegCloseKey(current); } } } // list_ports_friendly </code></pre>

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