I think it's clearly main() that "owns" that error, since it's the one that swallowed it. It would be impossible for the shell to own it since it's impossible for the shell to even detect it, given this program's buggy behavior.
I find the argument that the code obviously ignores the error so that's obviously the program's intent to be completely spurious. The code "obviously" intends to print the string, too, and yet in some cases, it doesn't actually do that. It's clearly a bug. I don't think it's particularly useful to harp on this bug in the most introductory program ever, but it's definitely a bug.
Definitely thought-provoking. A few responses here on HN disagree with calling this a bug, so maybe the user owns the error. This is all related to what kind of contract we have in mind when creating and using such a program.
If `puts` were to be used for debug messages, it might be right not to fail so as to not disturb the rest of the program. If the primary purpose is to greet the world, then we might expect it to signal the failure. But each creator or user might have their own expected behaviors.
If a user expects different behavior, then perhaps it is a feature request:
The question is how the behavior can be made more explicit. I think it's a reasonable default to make programs fail often and early. If some failure can be safely ignored, it can always be implemented as an (explicit) feature.
I find the argument that the code obviously ignores the error so that's obviously the program's intent to be completely spurious. The code "obviously" intends to print the string, too, and yet in some cases, it doesn't actually do that. It's clearly a bug. I don't think it's particularly useful to harp on this bug in the most introductory program ever, but it's definitely a bug.