How to create a custom daemon using shell scripts

Open a text editor and create a new file with a .sh extension (e.g., mydaemon.sh).

Write your shell script to perform the desired task. For example, let’s create a simple script that logs the current date and time to a file every minute:

#!/bin/bash
while true; do
echo "$(date)" >> /path/to/log/file.log
sleep 60 doneSave the file and make it executable by running chmod +x mydaemon.sh.Create a new file with a .service extension in the /etc/systemd/system/ directory.For example, mydaemon.service.Open the file in a text editor and add the following content:[Unit]
Description=My Custom Daemon
After=network.target
[Service] ExecStart=/path/to/mydaemon.sh
Restart=always
User=nobody
Group=nogroup

[Install]
WantedBy=multi-user.target

Replace /path/to/mydaemon.sh with the actual path to your shell script.Adjust the User and Group settings if needed.Run the following command to reload the systemd configuration and make it aware of your new service:sudo systemctl daemon-reloadStart your custom daemon using the following command:sudo systemctl start mydaemonTo make your daemon start automatically at system boot, enable it with the following command:sudo systemctl enable mydaemonCheck the status of your custom daemon with the following command:systemctl status mydaemonIf everything is set up correctly, you should see that your daemon is active and running.

That’s it! You have now created a custom daemon using a shell script and configured systemd to manage it. Your daemon will run continuously in the background, performing the specified task (in this example, logging the date and time every minute).

Remember to replace /path/to/mydaemon.sh with the actual path to your shell script and adjust any other settings according to your requirements.

Note: Be cautious when creating custom daemons and ensure that they don’t introduce security vulnerabilities or consume excessive system resources.