Windows key + dot, then type in warning / if it was among the last ones you used, use the arrow keys, and hit Enter to insert it.
If you use whatever OS other than Windows, I'm sure there are similar flows available if you search for it. And since it's just Unicode, I'm sure there are numpad based keybinds available too.
Emoji selector is fast and works perfectly fine over SSH, it's no different to any other input method that needs to use characters beyond 7-bit ASCII.
grep is a bit more iffy. UNIX command line tools seem to be a bit of a crapshoot in how or if they support Unicode, especially if you switch between different systems like Linux, BSD, Cygwin etc. You might need a bit of experimenting with the LANG variable to get it work (e.g. Git Bash on Windows needs LANG=C.UTF16 to match an emoji). I've also had cases where grep or sed works, but awk doesn't, or vice versa. On the whole it works a lot better nowadays than it used to, though, and that's a win for non-English users of the command line as well as emoji fans.
Didn't you ever grep a text document written in a language other than English? No processing of CSV files in different charsets? Not even encountered a file with a non-English character in the name? Not to mention the folks who deliberately set LANG so that their compiler and everything else will give them localized error messages. This stuff was all much worse 25 years ago, even 15 years ago. Like them or not, I do think emojis have helped drive forward much better Unicode handling across the whole stack, including the command line.
> Didn't you ever grep a text document written in a language other than English?
Yes but it was for humans originally? Not for machine processing.
> Not to mention the folks who deliberately set LANG so that their compiler and everything else will give them localized error messages.
The horror! Who even works on translations for compiler error messages ?!?
It makes absolutely no sense!
Next they'll want to localize programming language keywords. I wonder how well that will work at this current project of mine that has people native to 3 countries, none english speaking ...
How old? I'm old enough that my first Linux experience included a stack of floppy disks and recompiling a 0.9x kernel in late high school, and my first c++ program was done with Borland C++ 3.1. It never occured to me to look for a localized UI for either of them.
It's not a "what I think" thing, these were your literal words:
> How do you grep for it
And then how badly or well this works will depend on your build of grep and your environment variables, as the other user noted. I did not consider this, because I'd expect grep to just work with Unicode symbols like this when my stdin is set to UTF-8, which I'd further expect to always being the case in 2025, but it appears that's not an expectation one can reasonably have in the *nix world.
It was and continues to be unclear to me why you'd want to grep for the warning emoji though, since according to the article these are inserted somewhere deep in the console-visual explanations. They do not replace the slug denoting the compiler message type at the start of these, which as you said, can (still) be found by just grepping for "warning".
Oh but in the real world you vpn into a server that privately tailscales to some boxes that are hard to reach inside a factory and no one has physically touched them since 2018 at best ...
If you use whatever OS other than Windows, I'm sure there are similar flows available if you search for it. And since it's just Unicode, I'm sure there are numpad based keybinds available too.