a plea for better developmer documentation

This notion has been in my head for years, but seeing the instructions for Installing Rust on Linix made me want to write this down.

The cut-and-paste instructions are

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Now curl https://some.site/some.sh | sh is mildly spooky on its own, running a script from the internet. But, the Rust team has a good reputation and we can assume that the script is safe. But then why the additional flags on curl? What do they do? Why are they there? Do I need them?

The page gives no explanation. It just says “run this command” and leaves it at that. This is endemic in developer documentation.

curl options

• --proto '=https' - According to the man page the option “allows scripts to safely rely on being able to disable potentially dangerous protocols, without relying upon support for that protocol being built into curl to avoid an error. to only use the https protocol.” In the case of rust install command, this means that curl will complain if the URL https://sh.rustup.rs doesn’t begin with https:. Since we know exactly what the URL is, this is wholly unnecessary

TODO: I’m still working on this post. I have a lot more to say about this topic.

how this got to be this way

stateDiagram
    direction LR
    [*] --> A
    A --> B
    B --> C
    state B {
      direction LR
      a --> b
    }
    B --> D