Please try to forgive this slightly off-programming-topic question. At least I'm getting this problem when porting my C++ code to Linux. The problem I'm having is very basic: some key combinations are not recognized by emacs. One result of that is that I can't 'undo' edits in Emacs.
I'm running Putty.exe from Windows to my Ubuntu machine. The Putty character set (Window -> Translation -> received data char set) is UTF-8, and all my Swedish characters show up neatly on the console. When in Emacs however, I can't get C-_ to work. Nothing happens. The key combination on my Swedish keyboard is
Ctrl Shift -
Any pointers are helpful!
Try with just Ctrl and "-". I do not use emacs, but I use that key for screen(1) since it is not used for anything else (and the default of Ctrl-a is not so useful). On windows (with my Norwegian keyboard) the keypress to trigger it is just Ctrl-. In konsole windows in KDE Ctrl- will decrease font size, so there I have to fall back to Ctrl Shift - (it used to be just Ctrl- there as well some years ago).
When I'm editing with Swedish keyboard settings I have gotten used to undo with C-x u for reasons I can't remember anymore.
Related
I am trying to use org-mode and whenever I press Crtl+return emacs does C-J instead. I know this because when I use c-h k and then press crtl+return, emacs shows:
"It is bound to C-j."
Is there anyway I can make it register ctrl+return so I can insert headings?
I am using emacs23 through the terminal on ubuntu 12.04 x64. When I do this on my windows machine it does insert a new heading.
Possibly. As #phils says, C-Enter is usually not a valid sequence for the vast majority of terminal emulators. This is because when you press a key, or key combination, the terminal sends a sequence of characters to the relevant application. Pressing a sends a, whereas Enter sends CR - carriage return (otherwise known as ^M, \r or \015).
What sequences are actually implemented in modern terminals is mostly just a hang-over from the earlier, physical, terminals that they emulate (notably the VT-100). These machines didn't allow the use of Ctrl in conjunction with every key, such as the function keys, for example, so C-F1 was not possible and didn't have an escape sequence defined. Similarly, there is no control sequence for C-Enter, so when you press it, the terminal ignores the Ctrl and just sees the Enter.
You may, however, be able to define your own escape sequences in your terminal, which you can then bind to the correct key combinations in emacs. See here, for example. I was able to use this method to be able to use C-Enter. Unfortunately, this is still a bit of a pain, as it requires a lot of configuration and you may still be unable to use some sequences (C-M-% doesn't work in konsole for me). As with #phils, I've taken to using the GUI, but I'd love to have better integration with my terminal.
That's not a valid sequence for most terminals, I'm afraid, so they simply can't send it to Emacs.
If you run GUI Emacs instead, the key bindings will work.
Thomas Dickey's xterm is the only terminal software I know of which can (I think) support all the normal Emacs bindings. If you're okay with compiling that, then you could try it with the following .Xdefaults-(hostname) (or .Xresources if you re-merge after editing) to get basic support working:
XTerm*metaSendsEscape: true
XTerm*modifier: meta
XTerm*modifyOtherKeys: 1
You actually need XTerm*modifyOtherKeys: 2 to fully extend the sequences (otherwise you still can't type the likes of C-M-%), but by default that setting will break most key sequences, and right now I couldn't tell you how to configure things correctly for that setting (the only example I've seen -- xterm-extras.el as mentioned on the wiki and available in the easymacs download -- didn't work for me).
I mostly use GUI Emacs, but I'd love to get this working properly, so if anyone has had success with xterm-extras.el or similar, please do speak up.
If you're willing to install an Emacs package and configure your terminal, I wrote an Emacs package which can teach Emacs and terminals how to properly recognize all PC keyboard keys and modifier key combinations:
https://github.com/CyberShadow/term-keys
Its default configuration enables encoding the CtrlReturn combination, which allows Emacs to distinguish it from CtrlJ.
In org-mode, pressing M-S-RET (meta-shift-return) will create a new TODO on a new line. This key sequence sends M-RET to emacs through my terminal. I've checked this with C-h c ESC-S-RET, which returns M-RET is undefined in the mini-buffer.
I'm using Snow Leopard with Emacs 23.2.1 running in Terminal.app. There is no option to define a RET sequence in the terminal keyboard preferences.
Any idea what's causing the missing SHIFT? Workarounds?
You can get Emacs to pretend that it got S-RET with C-x # S RET (note uppercase S).
This also works for adding control, meta, alt, hyper or super modifiers; type C-x # C-h for the list of bindings. The Modifier Keys section in the Emacs manual mentions this as well.
In general, lots of keystrokes are simply impossible to send via a terminal, since terminals emulate an old protocol that only allowed 256 separate keys (or maybe only 128).
Chances are, when you press S-RET, Terminal.app does exactly the same thing as if you'd pressed RET. Thus Emacs has no way to distinguish those two cases.
Cross-linking to other Q&As:
If you are using an xterm, then the modifyOtherKeys option may facilitate that binding. See the following for details:
Send "C-(" to Emacs in VT100/xterm terminal (Mac OS X's Terminal)?
I suspect Emacs recognises those codes by default, but if not then also see input-decode-map as described here: Binding M-<up> / M-<down> in Emacs 23.1.1
See explanation and alternative shortcuts for TTY here.
Some of these have worked for me in a terminal in Ubuntu Linux (both locally and over SSH), but not all of them seem to work. For example, the alternative provided for S-RET (which I expected to run org-table-copy-down) instead seems to run org-clone-subtree-with-time-shift for some reason. However, I have found the list of alternatives useful, particularly those with the M- prefix. For example ESC UP for M-UP to move text around in tables.
In Haskell-mode, the shortcut C-c C-= is defined to do something.
Trying this shortcut, I realized that emacs do not recognize the shortcut C-c C-=.
Indeed, when I try the shortcut on emacs, the buffer write C-c = is not defined although I pressed C- C-=. I have the same problem with some other symbols like '.' or 'ยง'. But shortcuts like C-c C-l or C-c C-c work.
I try to remove my .emacs but I have the same problem.
a friend have the same problem as me.
Both we are on ArchLinux (64 bits) and we use emacs in console. The keyboard is an azerty.
The problem come from emacs ? Arch Linux ?
Your terminal can't send Emacs C-= so you can't use that key sequence. (Emacs would recognise it if it received it, but that won't happen.)
Your options are:
Run GUI Emacs.
Use M-x name-of-command RET (for whatever command is bound to the key sequence you're not able to use). Use C-hm to see the major mode's bindings, or C-hb to see all current bindings, in order to learn what those command names are.
Create new custom keybindings for the commands in question (i.e. bindings which your terminal can send to Emacs).
Find a different terminal emulator with enhanced key sequence abilities. The vast majority of them will be no better than what you have, because they're all adhering to the limitations of the terminals they're emulating. The most capable one I know of is http://invisible-island.net/xterm/xterm.html but you may need to compile it yourself, and then expect to spend lots of time configuring it. (It's not a trivial solution, though, and xterm requires a GUI environment, so running GUI Emacs is much simpler.)
Use C-x#c<key> instead of C-<key>.
With that last option, you can use a sequence your terminal can send to fake a sequence that it can't send.
C-cC-= would become C-cC-x#c=
If you really wanted to use that last option, you can set a custom binding to simplify the sequence (may be necessary in some instances to avoid conflicting with existing sequences). See the end of https://stackoverflow.com/a/24804434/324105 for more information.
To add to phils' post - another option is an Emacs package (which I wrote), which can teach Emacs and terminals how to properly recognize all PC keyboard keys and modifier key combinations:
https://github.com/CyberShadow/term-keys
The default configuration already includes encoding key combinations like Ctrl=, as well as similar variations.
I use urxvt (terminal) under awesome (window manager) and ubuntu (os).
In graphical mode, c- set the mark but in text mode it inserts a space.
The problem is solved when using gnome-terminal but some other key combinations still does not work. For instance, C-: insert a : in both terminals.
I do not know where to look at to correct this behaviour.
C-h k (help on key combination) followed by one of these combination shows only the key pressed along ctrl, for instance C- is interpreted as .
As stated in comments, the terminal is probably the cause. I believe that C- should not enter a space at the terminal prompt, which it does here.
I identified this question as being related. This one too.
In my case, Ctrl-Space was being used to change input methods. Running ibus-setup and unbinding it fixed my problem (it now produces Nul)
See also: https://askubuntu.com/questions/243639/ctrlspace-has-been-bound-to-invoke-some-input-method-and-does-not-work-in-ema
My problem is that I want to bind Control + Backspace combination to backward-delete-word function. However, it doesn't seem possible because emacs doesn't detect the Control key in combination with backspace.
I detected that by looking at the "logger" (C-h l). So if I press Backspace, it shows DEL. If I press Control + Backspace, it still shows DEL.
Is there any way to achieve that?
I have read and tried other questions, but couldn't fix it.
As #phils pointed out, if you are using Emacs in a terminal (e.g. emacs -nw) instead of as a GUI (no -nw command-line option), and if you are not on MS Windows, then by default certain key sequences are not available to you.
However, it might still be possible for you to configure the terminal (e.g., xterm) so that it in fact supports some such key sequences for Emacs. See this comment by the Emacs maintainer in the discussion of Emacs bug #10387.
(That said, you might find it simpler to just use a different key sequence. Or switch to the GUI version of Emacs.)