Start a new Bash command with nice value 10.
Do not change the nice value of the current shell.
Which command satisfies the requirement?
nice applies a nice value when it starts a new command. A positive value lowers CPU scheduling priority without changing the caller's shell.
Detailed explanation
renice --priority 10 --pid "$$"Incorrect. renice changes the current shell's priority rather than only the new command.
Incorrect. renice changes the current shell's priority rather than only the new command.
nohup bash -c 'ps -o ni= -p "$$"'Incorrect. nohup changes hangup handling but does not set a nice value.
Incorrect. nohup changes hangup handling but does not set a nice value.
nice -n -10 bash -c 'ps -o ni= -p "$$"'Incorrect. A negative nice value requests a higher priority and is the opposite of the requirement.
Incorrect. A negative nice value requests a higher priority and is the opposite of the requirement.
nice -n 10 bash -c 'ps -o ni= -p "$$"'Correct. nice starts the new Bash with nice value 10 while leaving the caller unchanged.
Correct. nice starts the new Bash with nice value 10 while leaving the caller unchanged.
Try it yourself
An example you can run in a temporary verification environment.
printf 'parent='; ps -o ni= -p "$$"
nice -n 10 bash -c 'printf "child="; ps -o ni= -p "$$"'
printf 'parent-after='; ps -o ni= -p "$$"Expected result
parent= 0
child= 10
parent-after= 0
※表示の空白幅は環境により異なるKey points
- nice versus renice
- Positive nice values
- The scope of a newly started process
Notes
- Environment: Bash 5.2 / GNU coreutils 9.x
- Command output formatting can vary slightly by distribution or tool version.
- Run the example in a temporary directory or process when possible.
Foundation review
Read the scope first
Check whether the command acts on the current shell, a new process, an existing process, or a file.
Verify the observable result
Use the supplied command and compare the output with the expected result.