How to Verify that at Access Is Denied

To verify that a username was added correctly to /etc/cron.d/at.deny, use the at -l command while logged in as the user. If the user cannot access the at command, the following message is displayed.

# su smith
Password:
$ at -l
at: you are not authorized to use at.  Sorry.

Likewise, if the user tries to submit an at job, the following message is displayed:

$ at 2:30pm
at: you are not authorized to use at.  Sorry.

This message confirms that the user is listed in the at.deny file.

If at access is allowed, the at -l command returns nothing.