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Here's how:
(1) Enter the command:
Nohup your shell Command &
(2) Enter the terminal back to the shell command line;
(3) Enter the Exit command to exit the terminal:
Exit
(4) You can now close your terminal software, wait for enough time, let your shell command after the execution and then go up to see the results.
The Nohup command allows your shell command to ignore the sighup signal, which can be removed from the terminal and "&" allows your command to run in the background.
Running shell commands in the background in an off-terminal way has several advantages: as long as you have executed the command, your network outage will not have any effect on you, and you can shut down the terminal software.
(turn) Linux to make shell commands out of the terminal running in the background