Beyond Linux® From Scratch - Version 7.9

Chapter 12. System Utilities

at-3.1.18

Introduction to at

The at package provide delayed job execution and batch processing. It is required for Linux Standards Base (LSB) conformance.

This package is known to build and work properly using an LFS-7.9 platform.

Package Information

at Dependencies

Required

An MTA

Optional

Linux-PAM-1.2.1

User Notes: http://wiki.linuxfromscratch.org/blfs/wiki/at

Installation of at

[Note]

Note

This package tarball has not been made from a directory. Unlike the normal packages in BLFS, you need to create a directory and untar into it: 

mkdir -v at-3.1.18 &&
cd       at-3.1.18 &&
tar -xf  ../at_3.1.18.tar.gz

Before building at, as the root user you should create the group and user atd which will run the atd daemon. Also ensure the working directory for the daemon exists: 

groupadd -g 17 atd                                                  &&
useradd -d /dev/null -c "atd daemon" -g atd -s /bin/false -u 17 atd &&
mkdir -p /var/spool/cron

Fix Makefile.in so that the documentation directory is installed in the specified docdir: 

sed -i '/docdir/s/=.*/= @docdir@/' Makefile.in

Install at with the following commands: 

./configure --with-daemon_username=atd        \
            --with-daemon_groupname=atd       \
            SENDMAIL=/usr/sbin/sendmail       &&

make

This package does not come with a test suite.

Now, as the root user: 

make install \
        docdir=/usr/share/doc/at-3.1.18 \
      atdocdir=/usr/share/doc/at-3.1.18

Configuring at

Config Files

/etc/at.allow and /etc/at.deny determines who can submit jobs via at or batch.

Boot Script

Install the /etc/init.d/atd init script from the blfs-bootscripts-20150924 package. 

make install-atd

Contents

Installed Programs: at, atd, atq (symlink), atrm (symlink), atrun, and batch
Installed Libraries: None
Installed Directories: /var/spool/cron/at{jobs,spool} and /usr/share/doc/at-3.1.18

Short Descriptions

at

queues, examines or deletes jobs for later execution.

atd

is the daemon that runs jobs queued for later execution.

atq

lists the user's pending jobs, or all jobs, if superuser.

atrm

deletes jobs, identified by their job number.

atrun

runs jobs queued for later execution.

batch

is a script that executes commands when system load levels permit.

Last updated on 2016-03-04 15:42:06 -0800