How to run on Headless Mac Mini M1 with nohup and screen

(1) Need a HDMI dummy simulator attached to Mac Mini for full speed operation. Be sure to have HDMI 2.0 and 4K support and some dummy simulators have Pass-Through EDID Emulator (also with 4K support) so that you can attach 4K monitor or via screen sharing in HD when working on it with attached keyboard and mouse.

(2) Disable sleep mode and set never sleep for HD and monitor on System Preferences of Mac Mini.

(3) Enable Sharing and SSH login on Mac Mini.

(4) generate ssh key-pair on mac mini and your terminal or your phone. If using Android phone, recommend Termux app for remote shell access.
e.g. ssh-keygen -t rsa # generate key pair on Mac Mini and remote client

(5) copy the ssh key-pair to mac mini if using another terminal from mac.
e.g. ssh-copy-id user@x.x.x.x

(6) Login in Mac Mini via ssh remotely
e.g. ssh user@x.x.x.x

(7) # Apple Compressor command line batch submission example (no need for nohup)
/Applications/Compressor.app/Contents/MacOS/Compressor -batchname "My First Batch" \
-jobpath ~/Movies/MySource_x265.mp4 \
-settingpath /Applications/Compressor.app/Contents/Resources/Settings/ProRes/proRes422Name.compressorsetting \
-locationpath ~/Movies/MyOutput_ProRes422.mov

(8) # install youtube-dl, prerequisite: Command Line Tools for Xcode 12.2 for Python 3.8 to be installed
sudo mkdir -p /usr/local/bin
sudo curl -L https://github.com/l1ving/youtube-dl/releases/latest/download/youtube-dl -o /usr/local/bin/youtube-dl
sudo chmod a+rx /usr/local/bin/youtube-dl
youtube-dl --version
sudo youtube-dl -U # update youtube-dl
youtube-dl --version # check version after update
cd $HOME/Downloads
mkdir -p youtube
cd youtube
youtube-dl -f mp4 <youtube url>

(9) Either use nohup or screen command for persistent jobs.

# nohup example
nohup bash -c 'youtube-dl -f 401 https://youtu.be/8rPB4A3zDnQ' &> nohup.youtubedl.4k_2.out &

(10)screen example (suitable for command utility with tty input
# create a screen and run python script
screen -S tensorflow
conda activate python38
python cnn.py
# leave (detach) the screen by Control-A d

# create second screen and run handbrake conversion
screen -S handbrake
conda deactivate
$HOME/Downloads/HandBrakeCLI -i $HOME/Downloads/8KVIDEO120FPS-8rPB4A3zDnQ_4.1G.mp4 -o $HOME/Downloads/8KVIDEO_x265.mp4 -e x265 -q24
# leave (detach) the screen by Control-A d

# list all the screen ids
screen -ls

# Reattach to one of the screen e.g. 6473.tensorflow
screen -r 6473

# Exit Screen if the process terimated
exit