Command to exit script but not the SSH session

Question

This is my first post here and I am not an expert of Linux /Bash scripting yet. :-)

So I wrote the following code for my Raspberry Pi and it works fine except for one small issue.

I am using SSH to log into the raspberry Pi.When pin 17 is high, ( digital logic value of 1 aka 5 volts ), I want the message “I noticed a 1” printed on the terminal output and then I want to exit the script and still stay logged into the raspberry Pi.

The problem that I am facing is when the script sees a logic value of 1, it shuts down the entire ssh connection adn takes me back to my laptop's terminal session.

I dont want the script to exit the ssh connection when pin 17 reads a 1. I just want it to stop executing the scriot and take me back to the raspberry Pi terminal where I am still logged into the raspberry Pi so that I can do other stuff.

I basically DO NOT want to close the SSH session when the scipt exits. Could you please give me some suggestions to fix this issue?

Thank you for the reply!

pin=17
gpio mode $pin in
while true; do
    if [[ $(gpio read $pin) -eq 1 ]]; then
        echo "I noticed a 1 whcih means I noticed 5 volts!"
        return
    elif [[ $(gpio read $pin) -eq 0 ]]; then
        echo "Did not see a 1, so I will keep looping"
        echo ""
        sleep 2
    fi
done

Answer 1

Welcome to Server Fault. Try using the following code:

pin=17
gpio mode $pin in
while true; do
    if [[ $(gpio read $pin) -eq 1 ]]; then
        echo "I noticed a 1 whcih means I noticed 5 volts!"
        kill -INT $$
    elif [[ $(gpio read $pin) -eq 0 ]]; then
        echo "Did not see a 1, so I will keep looping"
        echo ""
        sleep 2
    fi
done

Answer 2

I'm assuming you do something like

ssh raspberrypi /path/to/script

So, yes, when the script exits, the ssh session ends too.

However, in the script, instead of exiting, spawn an interactive shell:

    if [[ $(gpio read $pin) -eq 1 ]]; then
        echo "I noticed a 1 whcih means I noticed 5 volts!"
        exec bash -li

That replaces the running script process with an interactive login shell.

You might need ssh -t or ssh -tt, test without first.