terminal applications start blank

Question

I am using Kubuntu, 18.04. I have the following strange problem:
When launching any terminal application (Konsole, gnome-terminal, Dolphin file manager with am embedded console window) they start with a blank prompt.
Anything I type is shown, but has no "meaning" - that is, it is not taken as input by the shell.
I need to press Ctrl+C in order to get out of this state, and for the prompt resume normal operation.
My guess is that there must be some config file that tells terminal apps, which shell to start (and how), and my guess is that something changed there.
Does any of you know how to fix this?
Here is the output of Konsole when I launch it (same for all terminal applications):

This text has no effect after "enter"
as you can see.
Now I will press Ctrl+C:
^Cdkish@r2d2:~$ 

As you can see from the last line, only after the Ctrl+C the prompt appears, and from that point on everything works as normal.

Thanks in advance!

Answer 1

I think terminal applications usually start the terminal you specify in /etc/passwd. When you do a grep dkish /etc/passwd, what does the last part (the part after the last : character) say? I'm using bash, so on my system it gives /bin/bash. If it says something different, try editing this file. You'll need to logout+login for this to take effect I think.

Update You mention your Bash 'starts badly', but that /bin/sh is not affected. This could be an issue with Bash specific configuration files. ~/.bashrc and /etc/bash.bashrc come to mind. Check ~/.bashrc first. Does it contain a command that is waiting for input? Does it contain a long running command not set to run in the background?

Another way to check if those files are the culprit is to start a shell using /bin/sh and then manually start Bash using /bin/bash --norc. Does this give you a Bash that works without having to press Ctrl+C?