Strange thing happening in command prompt

Question

I'm using Ubuntu in command line mode, no GUI. I'm new to UNIX, so I'm a bit confused by something that just happened. I accidentally typed "suspend" instead of "pm-suspend", and my root~#: prompt disappeared. Now, whatever I try to enter just gives me a line break, and pressing keys like esc, gives me ^[, the arrow keys are all something along the lines of ^[^[[D. What can I do to return to the normal shell prompt?

Answer 1

suspend is a bash built-in command, what it does as per the man page is:

 suspend [-f]
          Suspend  the execution of this shell until it receives a SIGCONT
          signal.  A login shell cannot be suspended; the -f option can be
          used to override this and force the suspension.  The return sta‐
          tus is 0 unless the shell is a login shell and -f  is  not  sup‐
          plied, or if job control is not enabled.

Thus your shell is suspended and will be until you send it a SIGCONT signal. The behavior you see is because the shell is not interpreting those characters.

To fix this:

1. Go to another virtual console (press alt-F3 or something) and log in.

2. use pkill to send the CONT signal to all processes named bash. This won't affect other running shells but should "unstick" the stuck one.

   pkill -CONT bash