Emacs on Putty suddenly stopped accepting ctrl-space?

Weirdly, ctrl-space to start a mark works on the command line in putty and on X on the machine, just not in putty. What configuration did I break?

That other question doesn't apply, because the ctrl-space is sent to the command line in putty, just not to emacs.

Ctrl-space not getting through ssh

I am on windows 8 using GIT bash to access a remote server via ssh. When I press Ctrl+Space in emacs running locally in console (emacs -nw), everything works as expected. However, when going over ssh, Ctrl+Space simply inserts a space, while other commands like Ctrl+X work fine.

Why doesn't Ctrl+Space get through? I have considered switching to a different terminal, but I am also curios as to why this is happening.

 

Why do you think Ctrl+Space is actually send as such? It might not be 'getting through' because it is sent as a simple space. – Anthon Feb 21 '14 at 7:58

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  At some point in the chain (my keyboard to the process on the remote server) The sequence Ctrl+Space is getting transformed into just Space, and I'm fairly sure it's the fault of ssh, since no such transformation occurs before ssh is in the chain – Shelvacu Feb 21 '14 at 8:01 
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  I assumed that with locally you meant when using a keyboard connected to your remote server. If you suspect ssh, you could try and setup telnet and see if that doesn't have the problem if you go with telnet over a port forwarded with ssh (telnet in itself is not secure as your password could be spied). An ssh tunnel will not filter an that out of the telnet session. – Anthon Feb 21 '14 at 8:13

 

If you're running things through the windows "shell" (DOS box, whatever) -- from a command line, it's because the terminal doesn't have a special map for ctrl-space. An actual windows ssh client (putty, securecrt, etc.) handles the keyboard mapping itself, and will do what I assume you want done (send a null.)

 

• using putty has worked, but I still don't know why ssh in windows command line doesn't work. – Shelvacu Feb 25 '14 at 4:34

 

CTRL-SPACE

Is actually the same as

CTRL-@

I've had situations when space didn't work and then used @ which did, however less convenient to type.

 

 

Is it possible, you are running an implementation of zssh? According to the man page, Ctrl-Space is an escape sequence within a zssh session.

zssh behaves as an usual ssh session until the escape sequence is depressed ( default is ^@ which can be produced by pressing C-space, or C-2, or C-` ), which enables file transfer mode. A new prompt is then displayed, and commands can be executed locally to initiate file transfers (among other things). It roughly behaves as a local shell featuring line edition, history and completion (thanks to libreadline), globbing, and escape characters ( " ' and \ ).

 

 

reflink: https://unix.stackexchange.com/questions/116239/ctrl-space-not-getting-through-ssh