cards.c

    LONG         lRet = 0;
    SCARDCONTEXT hContext = 0;
    SCARDHANDLE  hCard = 0;
    DWORD        dwAP = 0;
    DWORD        dwReaders = 0;
    BYTE         pbSend[MAX_APDU_SIZE];
    BYTE         pbRecv[MAX_APDU_SIZE];
    DWORD        cbSend = 0;
    DWORD        cbRecv = 0;

    if ((lRet = SCardEstablishContext(SCARD_SCOPE_USER, 0, 0, &hContext)) != SCARD_S_SUCCESS) {
        printf("Error initializing SCard context (0x%08X)\n", lRet);
        return;
    }

    switch (lRet = SCardListReaders(hContext, NULL, NULL, &dwReaders)) {
    case SCARD_S_SUCCESS:
        break;
    default:
        printf("Error checking card readers (0x%08X)\n", lRet);
    case SCARD_E_NO_READERS_AVAILABLE:
        printf("No device found.\n");
        return;
    }

    WCHAR* mszReaders = new  WCHAR[dwReaders];

    if((lRet = SCardListReaders(hContext, NULL, mszReaders.data(), &dwReaders))!=SCARD_S_SUCCESS) {
        printf("Error listing card readers (0x%08X)\n", lRet);
        return;
    }
  
    for(int i= 0; i< (int)dwReaders;  i+= wcslen(mszReaders.data()+i)+1) {
        if(mszReaders[i] == '\0') continue;

        switch((lRet = SCardConnect(hContext, mszReaders+i, SCARD_SHARE_SHARED, SCARD_PROTOCOL_Tx, &hCard, &dwAP)))
        {
        case SCARD_W_REMOVED_CARD:
            continue;
        case SCARD_S_SUCCESS:
            break;
        default:
            printf("Error connecting to the card (0x%08X)\n", lRet);
            continue;
        } 
      
        printf("Reading card from device: %S\n",mmszReaders+i);
  
        // Get Data - Read card serial number
        memcpy(pbSend, "\xFF\xCA\x00\x00\x00", 5);
        cbSend = 5;
        cbRecv = MAX_APDU_SIZE;
        if ((lRet = SCardTransmit(hCard, SCARD_PCI_T1, pbSend, cbSend, NULL, pbRecv, &cbRecv)) != SCARD_S_SUCCESS)
            continue;
 
        printf("Card UID: ");
        for (DWORD i = 0; i < cbRecv - 2; i++)
        {
          printf("%02X", pbRecv[i]);
          if (i == cbRecv - 3) printf("\n");
        }

        SCardDisconnect(hCard, SCARD_LEAVE_CARD);

    }
    SCardReleaseContext(hContext);
    delete[] mszReaders;