[rav]

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).

[fjarlq]

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]

[bas]

Very informative. Thank you!

[sangeeth96]

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.