Finally, I solved my problem ... thanks for your answers ... I post the code here, it may be useful for someone ... with this code we can get all the hardware devices that are connected to our system.
HDEVINFO hDevInfo; SP_DEVINFO_DATA DeviceInfoData; DWORD i; // Create a HDEVINFO with all present devices. hDevInfo = SetupDiGetClassDevs(NULL, 0, // Enumerator 0, DIGCF_PRESENT | DIGCF_ALLCLASSES ); if (hDevInfo == INVALID_HANDLE_VALUE) { //Error handling here. printf("Error Details:[%s]\n","INVALID_HANDLE_VALUE"); return 1; } // Enumerate through all devices in Set. DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA); for (i=0;SetupDiEnumDeviceInfo(hDevInfo,i, &DeviceInfoData);i++) { DWORD DataT; LPTSTR buffer = NULL; LPTSTR hwbuffer=NULL; DWORD buffersize = 0; // // Call function with null to begin with, // then use the returned buffer size (doubled) // to Alloc the buffer. Keep calling until // success or an unknown failure. // // Double the returned buffersize to correct // for underlying legacy CM functions that // return an incorrect buffersize value on // DBCS/MBCS systems. // while (!SetupDiGetDeviceRegistryProperty( hDevInfo, &DeviceInfoData, SPDRP_HARDWAREID, &DataT, (PBYTE)buffer, buffersize, &buffersize)) { if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) { // Change the buffer size. if (buffer) LocalFree(buffer); // Double the size to avoid problems on // W2k MBCS systems per KB 888609. buffer = (char*)LocalAlloc(LPTR,buffersize * 2); } else { //Error handling here. //printf("Error Details:[%s]\n",GetLastError()); break; } } printf("Test Result:[%s]\n",buffer); if (buffer) LocalFree(buffer); } if ( GetLastError()!=NO_ERROR && GetLastError()!=ERROR_NO_MORE_ITEMS ) { // Error handling here. printf("Error Details:[%s]\n",GetLastError()); return 1; } // Cleanup SetupDiDestroyDeviceInfoList(hDevInfo); return 0;