tmux sends the keys to the window before the shell finishes loading

[wizche]

Resulting in the instance not starting properly. maybe should we add a sleep?

[0xricksanchez]

The TMUX/Screen interaction can indeed be a little finicky. It seemed to work fine on my end and I already experimented with some sleeps before but wasn’t quite satisfied with my approach. Happy to review a PR regarding that as well

[wizche]

What I do now is send a tmux send-keys -t $SESSION_NAME:$WINDOW_NAME "" C-m before the actual afl-fuzz command, that seems to fix the problem in my case. Here some ChatGPT suggestions:

• Set a flag in .bashrc

  # Signal that the shell is ready for tmux commands
  if [ -n "$TMUX" ]; then
  tmux wait-for -S shell_ready
  fi

  And wait for it: tmux wait-for shell_ready

• Read the content from the session until it makes sense:

  
  # Start a new tmux session
  tmux new-session -d -s mysession

Function to check if the target pane is ready

check_pane_ready() { tmux send-keys -t mysession "pwd" C-m # Run a harmless command sleep 0.1 # Small delay to give tmux time to process

Capture the last output from the pane

last_output=$(tmux capture-pane -t mysession -p -S -1)

# Check if the output of 'pwd' was captured (or other suitable prompt check)
[[ -n "$last_output" ]]

}

Loop until the shell prompt is ready

until check_pane_ready; do sleep 0.1 # Retry interval done

---
Not sure which want you wanna go, maybe keeping a sleep is enough? 
We don't actually care if the whole campaign start is delayed for a second.

[0xricksanchez]

We don't actually care if the whole campaign start is delayed for a second. That's what I'm thinking. If there's a significant delay upon startup, it should be communicated to the user so (like a visual indicator or whatever).

I think either solution could work. Something that checks for a sane state/output before continuing seems reasonable and good to debug if we need to make further adjustments eventually if this keeps being a problem.