`$RUNNER_OS`/etc environment variables not documented (GitHub Actions)

[jmarshall]

What article on docs.github.com is affected?

https://docs.github.com/en/actions/reference/environment-variables#default-environment-variables

What part(s) of the article would you like to see updated?

This StackOverflow answer claims that GitHub Actions workflow steps are provided with an environment variable $RUNNER_OS that contains the value of ${{ runner.os }}.

This is confirmed by a simple workflow that just prints out env | sort:

…
RUNNER_OS=Linux
RUNNER_PERFLOG=/home/runner/perflog
RUNNER_TEMP=/home/runner/work/_temp
RUNNER_TOOL_CACHE=/opt/hostedtoolcache
RUNNER_TRACKING_ID=github_069548eb-c4f3-4542-baac-43ed0d140801
RUNNER_USER=runner
RUNNER_WORKSPACE=/home/runner/work/pysam
…

It also appears to be confirmed by the runner source code; see https://github.com/actions/runner/blob/419ed24c1ee8c70eeb096570980e700e833f81f6/src/Runner.Worker/RunnerContext.cs#L13

The affected web page lists environment variables available to workflow steps, including $CI and many variables of the form $GITHUB_xyz. If (some of) these $RUNNER_xyz environment variables are also supported for use by workflow steps, it would be useful if they were added to this listing.

Additional information

This is somewhat related to the previously-reported #2031, but that issue was interpreted as being about the context expression ${{ runner.os }} rather than the environment variable $RUNNER_OS.

[welcome]

Thanks for opening this issue. A GitHub docs team member should be by to give feedback soon. In the meantime, please check out the contributing guidelines.

[janiceilene]

Thanks for opening an issue @jmarshall and looking for related issues 💖 I'll triage this for the team to take a look 👀

[straves16]

Thanks for reviewing docs related to my workflow api 💷💷💷💷💷💷💷💳

[BrucieBoy38]

I'm trying to locate some compound send from my Coinbase wallet address to my Coinbase trading wallet. It never went through and cb isn't helping much or it's me. If someone would be kind to help me retrieve my compound; I would donate some of it 100%. Ty. 🤞🤞🤙

[lecoursen]

Hi there! Thanks for pointing this out. We should add that environment variable to https://docs.github.com/en/actions/reference/environment-variables#default-environment-variables as you suggest. You or anyone else is welcome to open a PR doing so! ⚡

[jmarshall]

Only GitHub staff are in a position to confirm which of the seven RUNNER_* environment variables observed are intended to be supported for use in workflows.

Note that only three of the corresponding runner context properties are documented.

[BrucieBoy38]

On Thu, May 13, 2021 at 1:10 PM John Marshall ***@***.***> wrote: What does this mean? Or what should I do?

Only GitHub staff are in a position to confirm which of the seven RUNNER_*

…

environment variables observed are supported for use in workflows. Note that only three of the corresponding runner context properties <https://docs.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions#runner-context> are documented. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#6127 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ASFMGJA7VWZALXREF3IZMULTNQW3XANCNFSM44KSEGGQ> .

[janiceilene]

@jmarshall That's a good call! Could you check with our wonderful support team about whether or not that variable should be documented? If it is, you can either comment here and we'll reopen this issue or open a new issue 💖

Thanks so much for helping to improve the GitHub docs!