June 2017
Intermediate to advanced
478 pages
13h 14m
English
Content preview from Mastering Embedded Linux Programming - Second Edition
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
The init.d scripts
Each component that needs to respond to a runlevel change has a script in /etc/init.d to perform the change. The script should expect two parameters: start and stop. I will give an example of this later.
The runlevel handling script, /etc/init.d/rc, takes the runlevel it is switching to as a parameter. For each runlevel, there is a directory named rc<runlevel>.d:
# ls -d /etc/rc* /etc/rc0.d /etc/rc2.d /etc/rc4.d /etc/rc6.d /etc/rc1.d /etc/rc3.d /etc/rc5.d /etc/rcS.d
There you will find a set of scripts beginning with a capital S followed by two digits, and you may also find scripts beginning with a capital K. These are the start and kill scripts. Here is an example of the scripts for runlevel 5:
# ls /etc/rc5.d S01networking ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.