fg

Move background jobs to the foreground terminal to run

Summary

fg [job_spec ...]

The main purpose

• Used to put background jobs (jobs running in the background or suspended in the background) to the foreground terminal to run.

• If there is only one background task, the task number can be omitted when using this command.

Parameters

job_spec (optional): Specifies the job identifier to be moved to the foreground for execution, which can be one or more.

return value

Returns the execution status of the job, or returns failure if an error occurs.

example

#Run the sleep command and press ctrl+z.
sleep 60
^Z
[1]+ Stopped sleep 60

# Use the fg command to run the job in the foreground.
fg%1

# returned messages:
sleep 60

Notice

1. The job control commands of bash include bg fg kill wait disown suspend.
2. This command can only be executed when the set option monitor is turned on; to view the job control status: enter set -o to view the monitor line; execute set -o monitor or set -m to turn it on this option.
3. This command is a built-in bash command. For related help information, please see the help command.