Linux Survival Basics

Show the Real User Cron Jobs

You need to inspect a user's scheduled cron commands without editing the crontab.

Command

crontab -l | sed -n '/^[[:space:]]*#/d;/^[[:space:]]*$/d;p'

What changed

Nothing changes. The command prints the active, non-comment crontab lines.

Danger

safe

When to use it

Use when a job ran unexpectedly or did not run and you need the user's cron schedule first.

When not to use it

Do not use it as a full system scheduler audit; cron.d, cron.daily, and systemd timers live elsewhere.

Undo or recovery

No undo needed because the command is read-only.

Expected output

Environment assignments and active cron schedule lines.

demo script

Disposable terminal steps

crontab -l
crontab -l | sed -n '/^[[:space:]]*#/d;/^[[:space:]]*$/d;p'

Terminal transcript Demo JSON

simulated output

What it looks like

disposable vessel

::fixture-ready::
$ crontab -l
# user crontab for demo
SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
5 * * * * /usr/local/bin/check-disk >> /var/log/cron-disk.log 2>&1
17 2 * * * /usr/local/bin/backup-db
0 4 * * 0 /usr/local/bin/report-weekly | /usr/bin/mail -s report ops@example.invalid
::exit-code::0
$ crontab -l | sed -n '/^[[:space:]]*#/d;/^[[:space:]]*$/d;p'
SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
5 * * * * /usr/local/bin/check-disk >> /var/log/cron-disk.log 2>&1
17 2 * * * /usr/local/bin/backup-db
0 4 * * 0 /usr/local/bin/report-weekly | /usr/bin/mail -s report ops@example.invalid
::exit-code::0

YouTube Short

See active cron lines only.

Before editing cron, strip comments and blanks. Now you can see which jobs actually exist for this user.

experiments

A/B tests to run

Metric: save_rate

A: Stop opening cron in edit mode first.

B: Show active cron jobs without touching them.