[bug#43340] [PATCH 4/5] daemon: Spawn 'guix authenticate' once for all.

[Mathieu Othacehe]

> +                    (send-reply 500

Reply codes could be factorized in an enum.

> +    if (!agent) {
> +     Strings args = { "authenticate" };
> +     agent = std::shared_ptr<Agent>(new Agent(settings.guixProgram, args));
> +    }

make_shared should be preferred to the direct use of new.

> +         if (strchr("0123456789", ch)) {

You can maybe use isdigit?

Thanks,

Mathieu