**Use case**

It prints:
```
ClickHouse has been successfully installed.

Start clickhouse-server with:
 sudo clickhouse start
```

But if clickhouse-server is already running, let's print:
```
ClickHouse has been successfully installed.

Restart clickhouse-server with:
 sudo clickhouse restart
```
{
    auto sh = ShellCommand::execute(command);
    WriteBufferFromFileDescriptor wb_stdout(STDOUT_FILENO);
    WriteBufferFromFileDescriptor wb_stderr(STDERR_FILENO);
    copyData(sh->out, wb_stdout);
    copyData(sh->err, wb_stderr);
    if (throw_on_error)
    {
        sh->wait();
        return 0;
    }
    else
        return sh->tryWait();
}
static bool ask(std::string question)
{
    while (true)
    {
        std::string answer;
        std::cout << question;
        std::getline(std::cin, answer);
        if (!std::cin.good())
            return false;
        if (answer.empty() || answer == "n" || answer == "N")
            return false;
        if (answer == "y" || answer == "Y")
            return true;
    }
}
static bool filesEqual(std::string path1, std::string path2)