# getLicenseFileSerial static method

String getLicenseFileSerial()

Retrieves the serial number of the previously loaded license.

return The license serial number. throws DocumentException An error has occurred during Document Library execution.

## Implementation

    static String getLicenseFileSerial() {
      Pointer<Char> pLicenseFileSerial = calloc.allocate(256);
      Pointer<Int> pLicenseFileSerialSize = calloc.allocate(1);
      pLicenseFileSerialSize[0] = 256;
      try {
        var err = documentSDK.id3DocumentLicense_GetLicenseFileSerial(pLicenseFileSerial, pLicenseFileSerialSize);
        if (err == DocumentError.insufficientBuffer.value) {
          calloc.free(pLicenseFileSerial);
          pLicenseFileSerial = calloc.allocate(pLicenseFileSerialSize.value);
          err = documentSDK.id3DocumentLicense_GetLicenseFileSerial(pLicenseFileSerial, pLicenseFileSerialSize);
          if (err != DocumentError.success.value) {
            throw DocumentException(err);
          }
        }
        final vLicenseFileSerial = utf8.decode(Uint8List.fromList(pLicenseFileSerial.cast<Uint8>().asTypedList(pLicenseFileSerialSize.value)));
        return vLicenseFileSerial;
      } finally {
        calloc.free(pLicenseFileSerial);
        calloc.free(pLicenseFileSerialSize);
      }
    }