Emacs key bindings change in terminal emulator - emacs

I notice that some Emacs key bindings change in terminal emulator (xfce4-terminal).
For example: M-SPC under TTY sets the mark, but in xfce4-terminal it does nothing.
Also:
C-- is undo in TTY and does nothing in terminal emulator
C-/ is erase char backward in TTY, and undo in terminal emulator
Is there any solution to prevent the burden of learning two rules? I just want them as usual in TTY console.

It's not an Emacs problem so much as a terminal problem. Terminal emulators can be limited in the control and escape sequences they can send, so it's probably the case that the emulators you cited are swallowing your special characters before they even reach Emacs. Try hitting C-h l (or M-x view-lossage) to see if your key combinations are arriving in Emacs.
In addition to the answer that Legoscia cited, also check out this thread and this thread.
Unless you have a strong reason to stay in a terminal, you might consider running the GUI version and then running one of the various shells within it (eg, shell, eshell, ansi-term).

Related

Difference among Emacs org-mode in GUI, gnome-terminal and Guake terminal? [duplicate]

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.

emacs + konsole: key binding problems [duplicate]

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.

Some shortcuts don't work on emacs beginning with C-c

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 '§'. 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.

C-<SPC> is intercepted in emacs -nw (terminal intercept?)

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

M-RET and M-UP/DOWN not working in Emacs org-mode in console/terminal

I'm using emacs23 on Ubuntu 32-bit 10.04/10.10 with GNOME and Compiz.
Pressing M-RET in an org-mode plain list in Emacs (GUI) inserts a new item. Pressing M-Up moves the item up in the list.
These keys don't work as expected in emacs -nw under Terminator and gnome-terminal. The M-Up key does nothing, whereas the M-RET key simply moves the cursor down one line and indents the position. The keys also don't "work" in xterm, which inserts \215 instead. Pressing ESC-RET or ESC-Up instead produces the expected functionality. The same problems exist if I run emacs -nw on a headless server accessed via ssh under Terminator, gnome-terminal and xterm.
I've searched both generally and on the org-mode Gmane list for an answer to this, but have not found anything. Is this a known issue with org-mode or is it related to the terminal emulator and/or the Window Manager?
In addition to the keys in my question, S-TAB, S-Left, S-Right, S-Up and S-Down were not working over ssh and PuTTY. Using certain keys on a TTY connection (ssh, screen, PuTTY) is a known issue.
Alternative keys are included in org-mode as detailed in 'Using Org on a TTY' in the org-mode manual.
Alternative key combinations exist
for equivalent to M-RET
M C-m
"<return>" is the Return ↩ key while emacs runs in a graphical user interface.
"RET" is the Return ↩ key while emacs runs in a terminal.
"RET" is also equivalent to "C-m" (【Ctrl+m】). (http://ergoemacs.org/emacs/emacs_key_notation_return_vs_RET.html)
as equivalents for M-<up/down> you can use
ESC-<up>
ESC-<down>
The menubar of terminal emulator is not letting the M key that is meant for Emacs be passed down to Emacs. For Emacs to receive the M key as it is supposed to, you could either use the Esc or disable the menubar and use M key in Emacs as usual.
ADDED:
For the xterm, if you do CTRL+Mouse Button 1, you will see "Meta sends Escape". You need to make sure that option is checked/enabled to make M work as it should in Emacs.