This command runs your shell script in the background with no output of any kind, and it will remain running even after you logout.

Check out the usage of 'trap', you may not have seen this one much. This command provides a way to schedule commands at certain times by running them after sleep finishes sleeping. In the example 'sleep 2h' sleeps for 2 hours. What is cool about this command is that it uses the 'trap' builtin bash command to remove the SIGHUP trap that normally exits all processes started by the shell upon logout. The 'trap 1' command then restores the normal SIGHUP behaviour. It also uses the 'nice -n 19' command which causes the sleep process to be run with minimal CPU. Further, it runs all the commands within the 2nd parentheses in the background. This is sweet cuz you can fire off as many of these as you want. Very helpful for shell scripts.

This is helpful for shell scripts, I use it in my custom php install script to schedule to delete the build files in 3 hours, as the php install script is completely automated and is made to run slow. Does require at, which some environments without crontab still do have. You can add as many commands to the at you want. Here's how I delete them in case the script gets killed. (trapped) atq |awk '{print $1}'|xargs -iJ atrm J &>/dev/null

Run "ps -x" (process status) in the background every hour (in this example). The outputs of both "nohup" and "ps -x" are sent to the e-mail (instead of nohup.out and stdout and stderr). If you like it, replace "ps -x" by the command of your choice, replace 3600 (1 hour) by the period of your choice. You can run the command in the loop any time by killing the sleep process. For example ps -x 2925 ? S 0:00.00 sh -c unzip E.zip >/dev/null 2>&1 11288 ? O 0:00.00 unzip E.zip 25428 ? I 0:00.00 sleep 3600 14346 pts/42- I 0:00.01 bash -c while true; do ps -x | mail (...); sleep 3600; done 643 pts/66 Ss 0:00.03 -bash 14124 pts/66 O+ 0:00.00 ps -x kill 25428 You have mail in /mail/(...) Show Sample Output

After you execute a command (or shell script) in the background using &, if you logout from the session, the command will get killed. To avoid that, you should use nohup as shown below.

Starts qbittorrent-nox (or any other program) and dettach it from the terminal it was ran in. When you exit, the program keeps running. Show Sample Output

Run a nohup script in background launched trough a shell script without interrupting the main shell script execution.

If $INBACK is set, command will launch in foreground and inverse. Very useful in script ! We could apply the inverse comportement like that : eval command ${INBACK:+&}