Open System Services Management and Operations Guide (G06.30+, H06.08+, J06.03+)

The at command and the cron process use these files to determine whether and what commands
to run:
DescriptionFile
Lists the commands to be run once./var/spool/cron/atjobs/at
Lists the user IDs that are allowed to change the at file./usr/lib/cron/at.allow
Lists the user IDs that are denied access to the at file./usr/lib/cron/at.deny
You can use the at command if your login name appears in the /usr/lib/cron/at.allow
file. If that file does not exist, the at command checks the /usr/lib/cron/at.deny file to
determine whether your login name is denied access to at. If neither file exists, only a user who
has appropriate privileges can submit a job. If the at.allow file does exist, it must include the
login name of a user who has appropriate privileges to use the at command.
The at command also allows you to:
• Specify a file to be used as input instead of the standard input file
• Find out information about jobs that are queued
For more information about the at command, see the at(1) reference page either online or in
the Open System Services Shell and Utilities Reference Manual.
The atq Command
The atq command prints the queue of jobs that were created using the at command and are
waiting to be run at a later time. If you have appropriate privileges and you specify one or more
user names, only jobs belonging to those users are displayed. If you do not specify any user names,
a list of all jobs submitted is displayed.
The atq command allows you to sort the output in chronological order based on the time that the
at command was issued. You can also specify which queue you want to have printed.
For more information about the atq command, see the atq(1) reference page either online or
in the Open System Services Shell and Utilities Reference Manual.
The atrm Command
The atrm command removes jobs queued by the at command. If you specify job numbers, atrm
attempts to remove only those jobs. If you specify user names, atrm removes all jobs belonging
to those users.
For more information about the atrm command, see the atrm(1) reference page either online
or in the Open System Services Shell and Utilities Reference Manual.
The batch Command
The batch command runs commands at a system-determined later time and when the system
workload level permits. The batch command is equivalent to the following at command:
at -q b now
where queue b is an at queue for batch jobs.
For more information about the batch command, see the batch(1) reference page either online
or in the Open System Services Shell and Utilities Reference Manual.
Using the NetBatch Product
To use the NetBatch or NetBatch Plus product to schedule programs successfully, you need to know:
• OSS programs that use the OSS file system can open local terminal windows and local disk
files when started using this method. Remote devices, processes such as the spooler, and
Scheduling Periodic Tasks 75