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Comment by sangeeth96 | Hacker News Reader

It's frustrating this is not the same behavior on macOS: https://unix.stackexchange.com/a/774145

It seems to me that macOS has env -S as well, but the shebang parsing is different. The result is that shebang lines using env -S are portable if they don't contain any quotes or other characters. The reason is that, running env -S 'echo a b c' has the same behavior as running env -S 'echo' 'a' 'b' 'c' - so simple command lines like the one with uv are still portable, regardless of whether the OS splits on space (macOS) or not (Linux).

This is true. For example, the following shebang/uv header works on both macOS and Linux:

  #!/usr/bin/env -S uv --quiet run --script
  # /// script
  # requires-python = ">=3.13"
  # dependencies = [
  #     "python-dateutil",
  # ]
  # ///
  #
  # [python script that needs dateutil]

Very informative. Thank you!

True, this should be fine for straightforward stuff but extremely annoying as soon as you have for eg, quoted strings with whitespace in it which is where it breaks. Have to keep that difference in mind when writing scripts.

The link I posted in my original reply has a good explanation of this behavior. I was the one who asked the question there.

Maybe this helps? Have not tried it. https://blog.winny.tech/posts/multiple-arguments-in-shebang/

`brew install coreutils` and update your `PATH`.

I'm aware of this package for getting other utilities but:

1. I'm worried about this conflicting/causing other programs to fail if I set it on PATH. 2. This probably doesn't fix the shebang parsing issue I mentioned since it's an OS thing. Let me know if that's not the case.

You've got nothing to worry

Been doing it for more than a decade and yet to get in trouble. Not one issue. Doing it consistently for my teams as we decrease cognitive load (developing on macs but targeting unix). Others would confirm https://news.ycombinator.com/item?id=17943202

Basically software will either use absolute paths i.e. wants to use your OS version for a dependency like grep, or will use whatever grep is in your $PATH and stick to safe invocations regardless if it's BSD/GNU or if it's version x or y

Hmm, I haven’t run this experiment myself but I have in the past faced problems overriding default python/ruby commands in PATH that caused some stuff to fail and had to add some specific overrides for `brew` command, for example.

> Basically software will either use absolute paths

I’ve personally written scripts that break this assumption (that’s a me problem, I guess) so I am quite sure there’s a lot of scripts at the very least that do this.

Nevertheless, you’ve given me something to consider.

The PATH is irrelevant, this is about how the kernel parses the shebang. It starts exactly /usr/bin/env with two arguments, not some other env binary you might have in your PATH.

You can also brew install the gnu tools package and have both side by side for compatibility (gnu tools are prefixed with 'g', gls, gcat, etc

I have a script that toggles the prefix on or off via bash aliases for when I need to run Linux bash scripts on a mac.

And that on Android env doesn't live in /bin/.

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