How can I run anacron in user mode?

Question

I would like to set up a scheduled task via anacron but I would like to do so in user mode. How can I achieve this?

Answer 1

You can set up a separate anacron instance to run in user mode:

1. Create a .anacron folder in your home directory and in it two subfolders, etc and spool:

   mkdir -p ~/.anacron/{etc,spool}
   

2. Create a new file ~/.anacron/etc/anacrontab with contents similar to the following:

   # /etc/anacrontab: configuration file for anacron
   
   # See anacron(8) and anacrontab(5) for details.
   
   SHELL=/bin/bash
   PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
   
   # period  delay  job-identifier  command
   1         10     testjob         test.sh
   

3. Add the following line to your crontab using crontab -e:

   @hourly /usr/sbin/anacron -s -t $HOME/.anacron/etc/anacrontab -S $HOME/.anacron/spool
   

Answer 2

The anacrontab shown above has a problem: anacron looks for executables only in the directories specified in PATH. So it will not find test.sh.

A better solution is to use the command run-parts:

# /etc/anacrontab: configuration file for anacron
See anacron(8) and anacrontab(5) for details.
SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
period  delay  job-identifier  command
1         10     dailyjob        run-parts ${HOME}/.anacron/daily/

This requires that we create the directory daily:

mkdir -p ~/.anacron/{etc,spool,daily}

run-parts will not execute scripts with '.' in the name, such as "test.sh", so rename the script to, for example, "my-test".

There is yet another wrinkle: If the computer does not run 24/7, then one does not have control over at what time the daily script is run. I have a web scraping script that I want to be run at about 11 am, or later during the day. I fix this problem by scheduling the web scraping job in the "at" facility (sudo apt install at).

So I have a script daily/crawl which looks as follows:

#!/bin/bash
preferred_time="11:15"
scheduled_time="${preferred_time}"
preferred_time_as_number="${preferred_time/:/}"
current_time_as_number=$(date +%H%M)
if [ "${current_time_as_number}" -ge "${preferred_time_as_number}" ]; then
    scheduled_time="NOW"
fi
at -M -f "${HOME}/bin/crawl-dagpris.sh" "${scheduled_time}"

Answer 3

This worked for me (thanks), but I didn't use the last step given in the answer:

Then add the following line to your ~/.profile:

I'm using Ubuntu Studio 12.10 Quantal and in my case instead of that last step I put that one liner here: “Applications Menu” → “Settings” → “Settings Manager” then in the Settings Manager under “Session and Startup” then the “Application Autostart” tab.

This is for those of us that are GUI users, because ~/.profile is only sourced by bash when it starts a log-in interactive shell (even ~/bashrc is not so useful since that is only sourced when bash is starting an interactive shell).