atq shows unwanted job ID 42.
Remove only job 42 and keep other queued jobs.
Which command is appropriate?
atrm JOB_ID removes one queued at job; the ID is not a process PID.
Detailed explanation
atrm 42Correct. atrm 42 removes the queued at job with ID 42.
Correct. atrm 42 removes the queued at job with ID 42.
atq 42Incorrect. atq lists jobs rather than deleting one.
Incorrect. atq lists jobs rather than deleting one.
crontab -r 42Incorrect. crontab -r operates on cron entries.
Incorrect. crontab -r operates on cron entries.
kill 42Incorrect. kill treats 42 as a PID, not an at job ID.
Incorrect. kill treats 42 as a PID, not an at job ID.
Try it yourself
An example you can run in a temporary verification environment.
printf '%s\n' 'job id: 42' 'remove command: atrm 42'Expected result
job id: 42
remove command: atrm 42Key points
- Argument is job ID
- Not a PID
- Confirm with atq
Notes
- Environment: 合成ジョブ番号による構文確認
- 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.