final String appType = System.getenv(FESS_APP_TYPE);
        if (StringUtil.isNotBlank(appType)) {
            return appType;
        }
        return StringUtil.EMPTY;
    }

    public static OptionalEntity<String> getOverrideConfPath() {
        if (FESS_APP_DOCKER.equalsIgnoreCase(getAppType())) {
            final String confPath = System.getenv(FESS_OVERRIDE_CONF_PATH);

例如，您可以有一个名为 `main.py` 的文件，其中包含以下内容：

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

!!! tip
    <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的第二个参数是要返回的默认值。

    如果没有提供默认值，默认为 `None`，此处我们提供了 `"World"` 作为要使用的默认值。

然后，您可以调用该 Python 程序：

  // staleness (seconds) if provided.
  const char* block_size_env = std::getenv(kBlockSize);
  if (block_size_env && absl::SimpleAtoi(block_size_env, &value)) {
    block_size = value * 1024 * 1024;
  }
  const char* max_bytes_env = std::getenv(kMaxCacheSize);
  if (max_bytes_env && absl::SimpleAtoi(max_bytes_env, &value)) {
    max_bytes = static_cast<size_t>(value * 1024 * 1024);

    }

    public static List<Map<String, String>> getEnvItems() {
        final List<Map<String, String>> itemList = new ArrayList<>();
        for (final Map.Entry<String, String> entry : System.getenv().entrySet()) {
            itemList.add(createItem(entry.getKey(), entry.getValue()));
        }
        return itemList;
    }

    public static List<Map<String, String>> getPropItems() {

🖼 👆 💪 ✔️ 📁 `main.py` ⏮️:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

!!! tip
    🥈 ❌ <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 🔢 💲 📨.

    🚥 🚫 🚚, ⚫️ `None` 🔢, 📥 👥 🚚 `"World"` 🔢 💲 ⚙️.

⤴️ 👆 💪 🤙 👈 🐍 📋:

                System.getProperties().entrySet().stream().forEach(e -> logger.debug("Property: {}={}", e.getKey(), e.getValue()));
                System.getenv().entrySet().forEach(e -> logger.debug("Env: {}={}", e.getKey(), e.getValue()));
                logger.debug("Option: {}", options);
            } catch (final Exception e) {
                // ignore
            }

    }
}


private
fun makePropagatedEnvironment(): Map<String, String?> {
    val result = HashMap<String, String?>()
    for (key in propagatedEnvironmentVariables) {
        val value = System.getenv(key)
        if (value != null) {
            result[key] = value
        }
    }
    return result

        logger = LogManager.getLogger(loggerName);
        final String logFormat = ComponentUtil.getFessConfig().getAppAuditLogFormat();
        if (StringUtil.isBlank(logFormat)) {
            useEcsFormat = "docker".equals(System.getenv("FESS_APP_TYPE"));
        } else if ("ecs".equals(logFormat)) {
            useEcsFormat = true;
        }
    }

    public void login(final OptionalThing<FessUserBean> user) {

                System.getProperties().entrySet().stream().forEach(e -> logger.debug("Property: {}={}", e.getKey(), e.getValue()));
                System.getenv().entrySet().forEach(e -> logger.debug("Env: {}={}", e.getKey(), e.getValue()));
                logger.debug("Option: {}", options);
            } catch (final Exception e) {
                // ignore
            }

		fmt.Fprintf(os.Stderr, "adb %s\n%s", strings.Join(args, " "), out)
		return err
	}
	return nil
}

func adbCmd(args ...string) *exec.Cmd {
	if flags := os.Getenv("GOANDROID_ADB_FLAGS"); flags != "" {
		args = append(strings.Split(flags, " "), args...)
	}
	return exec.Command("adb", args...)
}

const (
	deviceRoot   = "/data/local/tmp/go_android_exec"