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Comment by jandeboevrie | Hacker News Reader

Those you might expect on a modern Linux system when bash is there (coreutils will be there 99% of the time as well). Not all distros ship curl by default

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Bash runs on a lot more than Linux.

I ran a Docker container and copied a statically-linked curl and bash onto a scratch image and ran it, it does not work:

    $ docker run -it --rm  $(docker build -q .)
    /srvmon.sh: line 162: date: command not found

    $ cat Dockerfile
    FROM scratch
    COPY bash /usr/bin/bash
    COPY curl /usr/bin/curl
    COPY srvmon.sh /srvmon.sh
    CMD ["/usr/bin/bash", "/srvmon.sh"]

I'm not pointing this out to be pedantic. I'm pointing it out because there is a common misconception that all these things like "date" and "cat" and "mkdir" are part of Bash, but they're not, they're part of coreutils and there are dramatically different versions of coreutils on different installations of Linux, macOS, BSD, etc., and some environments (like barebones Docker containers) don't have coreutils at all.

People who use containers where they aren't required or even sensible deserve, and should expect, what they intentionally get. Yours is not an argument showing that coreutils aren't everywhere. They are. It only shows that you specifically went out of your way to create an obscure environment designed explicitly to not have what it needed.

Agree with superkuh in this point. If you only have a hammer every problem looks like a nail. But I've updated the Readme with coreutils as a dependency.

My argument isn’t about containers, I was using that as an easy way to illustrate my point.

I care about this because I deal with it all the time. Coreutils programs have pretty different behavior across distributions and OSs, we shouldn’t sweep implicit dependencies under the rug.

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