#include <iostream>
#include <cstdlib> // 包含获取环境变量所需的头文件

int main() {
    // 要获取的环境变量的名称
    const char* envVarName = "MY_ENV_VARIABLE";

    // 使用std::getenv获取环境变量的值
    const char* envVarValue = std::getenv(envVarName);

    if (envVarValue != nullptr) {
        std::cout << "Environment variable " << envVarName << " has value: " << envVarValue << std::endl;
    } else {
        std::cerr << "Environment variable " << envVarName << " is not defined." << std::endl;
    }

    return 0;
}