Ah, yes - I have come across some differences in command-line flags and default behaviors between macOS and the nominally equivalent tools as implemented in Linux or specified by Posix, and sometimes, on Stack Overflow, you will find people answering Mac-specific questions on the Dunning-Krugeresque assumption that it is the same as the others. In general, one should always verify Stack Overflow answers before using, but that often gets you closer to the answer you need than one starting from a scenario that simply isn't available on your version of, say, Xcode.
The same goes for systems derived from BSD - in fact, I wonder if some of the differences between MacOS and Linux comes from the former's origins in Mach/BSD via Nextstep.
> I wonder if some of the differences between MacOS and Linux comes from the former's origins in Mach/BSD via Nextstep.
My understanding was that this is most of it. The problem is relatively basic—macOS uses the BSD versions of most unix tools, which means basic commands like sed sometimes function quite differently!
