Exercise 1: Rescuing top With reptyr — Possible Solution
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Terminal A (not in screen):

  $ top
  ^Z                                  (press Ctrl-Z)
  [1]+  Stopped                 top
  $ bg
  [1]+ top &
  $ jobs -l
  [1]+ 90213 Stopped (tty output)  top
  $ disown %1

  Note: top is an interactive, full-screen program, so in the
  background it stops again as soon as it tries to use the terminal
  ("Stopped (tty output)" or similar). That's fine — reptyr will wake
  it up on its new terminal.

Terminal B:

  $ screen -S rescue
  $ reptyr 90213

If you see an error such as "Unable to attach to pid 90213: Operation
not permitted", ptrace is restricted:

  $ cat /proc/sys/kernel/yama/ptrace_scope
  1
  $ sudo reptyr 90213        # or temporarily set the scope to 0

top now fills the screen window (press Ctrl-L if it needs a redraw).

Prove it survives:

  Ctrl-a d                   # detach in terminal B
  (close terminal A completely)
  $ screen -r rescue         # top is still running and updating

WHY THIS WORKS AS AN ANSWER
------------------------------
It follows the full sequence, shows the most common failure (ptrace
permission) and how to fix it, and ends with a real test: closing the
original terminal. The exact error wording and job states vary between
versions.