运行无效命令 C++ 时优雅退出

Question

我正在使用 boost 从我的应用程序运行命令行命令。我正在使用以下已封装到辅助函数中的代码：

tuple<string, int> Utility::RunCommand(const string& arguments) const
{
    string response;
    int exitCode;
    try
    {
        ipstream iStream;
        auto childProcess = child(arguments, std_out > iStream);
        string line;

        while (getline(iStream, line) && !line.empty())
        {
            response += line;
        }

        childProcess.wait();
        exitCode = childProcess.exit_code();
    }
    catch (...)
    {
        // log error
        throw;
    }

    return make_tuple(response, exitCode);
}

现在我有一个只能在具有某些属性的机器上运行的命令。此方法返回这些机器上的预期响应和错误代码。在其他机器上，它会抛出异常。

我尝试在应该失败的机器上手动运行该命令，它会返回以下输出：

POWERSHELL
PS C:\Users\xyz> dummy-cmd
dummy-cmd : The term 'dummy-cmd' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ dummy-cmd
+ ~~~~~~~~~~
    + CategoryInfo          : ObjectNotFound: (dummy-cmd:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

COMMAND PROMPT
C:\Users\xyz>dummy-cmd
'dummy-cmd' is not recognized as an internal or external command,
operable program or batch file.

如何让它运行，使其返回非零错误代码而不是抛出异常？

Answer 1

这就是您的catch 子句的用途，用于处理异常。它不必重新抛出它们：

tuple<string, int> Utility::RunCommand(const string& arguments) const
{
    string response;
    int exitCode;
    try
    {
        ipstream iStream;
        auto childProcess = child(arguments, std_out > iStream);
        string line;

        while (getline(iStream, line) && !line.empty())
        {
            response += line;
        }

        childProcess.wait();
        exitCode = childProcess.exit_code();
    }
    catch (PlatformNotSupportedException& e)
    {
        std::cerr << "That operation is not supported on this platform." << std::endl;
        exit(1);
    }
    catch (...)
    {
        std::cerr << "Unspecified error occurred." << std::endl;
        exit(1); // give nonzero exit code
        //throw; // take out this
    }

    return make_tuple(response, exitCode);
}