Run a command immune to hangups, with output to a non-tty
The nohup command allows you to run a program in a way that ignores hangup (SIGHUP) signals, ensuring that the process continues running even after the user logs out. The output of the command is typically redirected away from the terminal.
Whether or not the output is explicitly redirected by the user, nohup will attempt to append output to a file named nohup.out in the current directory. If the current directory is not writable, it redirects output to $HOME/nohup.out. If neither file can be created or opened, the command will not run. If standard error is a terminal, it is redirected to the same file descriptor as standard output.
nohup [options] [command [args]...]
--help: Display help information.
--version: Display version information.
Command and Options: The program to be executed and its arguments.
Submit a job using nohup. By default, all output is redirected to nohup.out unless an output file is specified:
nohup command > myout.file 2>&1 &
In the example above, output is redirected to myout.file.
Download a file in the background without hanging up:
nohup wget site.com/file.zip &
The following command generates a nohup.out file in the current directory containing the program's output:
nohup ping -c 10 baidu.com &
Simple background execution:
nohup command &
Redirect output to nohup.out in the current directory by default:
nohup python main.py &
Specify a custom output file (merging standard output and standard error into main.log):
nohup python main.py >> main.log 2>&1 &
Shorthand for the above (merging both outputs):
nohup python main.py &> main.log &
Discard all output:
nohup python main.py &> /dev/null &
Discard output and save the process ID (PID) to pidfile.txt for easier management:
nohup python main.py &> /dev/null & echo $! > pidfile.txt