How to leave the execute prompt in zsh

promptzsh

In a zsh, maybe I pressed Alt+X by mistake,
but now I'm stuck and this execute: _ prompt won't leave.

Pressing Ctrl+C does nothing.
If I press Enter it tries to complete what I typed.

Pressing Enter on an empty line:

execute: _
zsh: do you wish to see all 373 possibilities (64 lines)?

Typing q and pressing Enter:

execute: quote_
quoted-insert  quote-line     quote-region

In other shells, Alt+X brings the same behavior,
except that Ctrl+C cancels the prompt.

Is there a way to get out or is this shell dead?

Ctrl+G aborts the current editing command in Bash and Zsh if you are in Emacs mode (which is usually the default mode).

TL;DR

All you need to do is put this in your ~/.zshrc (or in the same file as your prompt theme):

ZLE_RPROMPT_INDENT=0

In versions of ZSH leading up to 5.0.2 a value in ZSH's C source code called rprompt_off (which set the right-margin offset) was hard-coded to 1.

But in the 5.0.5 release the developers added the ability to override this default value by setting the ZLE_RPROMPT_INDENT environment variable.

The rationale for this "indent" is because some older terminals would start scrolling if the last cell of the display had a character in it.

If you're on an older version of ZSH and can't update, you can still get rid of that space by doing both of the following:

Trick ZSH into thinking your RPROMPT is a character shorter than it actually is using the standard invisible sequence wrapper: %{...%}
Then sending a cursor-back escape sequence using terminfo: %{terminfo[cub1]}

Check out the FAQ and this message on the mailing list for more info.