On Mon, Mar 27, 2023 at 08:45:18PM +0100, debian-u...@howorth.org.uk wrote: > Greg Wooledge <g...@wooledge.org> wrote: > > Just to be clear, are you using some kind of Desktop Environment > > specific means of entering these Unicode characters? I don't know > > what CTRL-SHIFT-Uunicode means. If I try it here, it just gets > > interpreted as Ctrl-U which kills the line I'm typing in vim. > > No, he's using a standard keyboard mechanism which works well inside > gvim here for example, or in a normal terminal (lxterminal to be > precise). You hold down CTRL and SHIFT and then press U. You should see > an underlined lower case letter U. Now type the four digit code, e.g. > 2660. You will see the digits be echoed, also underlined and perhaps > with a coloured background. Now press ENTER and the whole lot is > magically replaced with a 'black spade suit' glyph.
I tried this in rxvt(-unicode), xterm, and lxterm (which is apparently part of the xterm package -- never heard of it before!). In all 3 terminals, Ctrl-Shift-U simply acts like Ctrl-U. If there's already text typed at the bash prompt, it's all erased. If there's no text typed at the bash prompt, it beeps. Interstingly, though, in rxvt-unicode, if I only press Ctrl-Shift and skip the U, a small region of the terminal window (lower left corner, which is annoyingly right where the cursor is) is colored yellow and says "ISO 14755 mode". If I keep holding Ctrl-Shift and type 2660 then the yellow region gets bigger and shows lots of text, including a spade character. When I release the Ctrl and Shift keys, the yellow goes away, and I'm left with just a spade character typed into the shell. This is a feature I was not previously aware of. It also doesn't work in xterm or lxterm. You spoke of gvim, which I don't have installed, but which I'm fairly sure is a GUI program. So, I tried a GUI program -- Google Chrome. I opened a new tab and went to google.com which I know has a text entry widget. In the text entry widget, I tried this Ctrl-Shift-U thing, and there, it works as you claimed it should. Space and Enter both seem to terminate the Unicode entry. "x" does not. It also works in Firefox. So it looks like this "standard keyboard mechanism" is part of some GUI toolkit, either X11, or GTK+, or something along those lines. It definitely doesn't work in a regular X terminal, nor would I expect it to.
