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You're reading from  Mastering Embedded Linux Programming - Third Edition

Product typeBook
Published inMay 2021
PublisherPackt
ISBN-139781789530384
Edition3rd Edition
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Authors (2):
Frank Vasquez
Frank Vasquez
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Frank Vasquez

Frank Vasquez is an independent software consultant specializing in consumer electronics. He has over a decade of experience designing and building embedded Linux systems. During that time, he has shipped numerous devices including a rackmount DSP audio server, a diver-held sonar camcorder, and a consumer IoT hotspot. Before his career as an embedded Linux engineer, Frank was a database kernel developer at IBM where he worked on DB2. He lives in Silicon Valley.
Read more about Frank Vasquez

Chris Simmonds
Chris Simmonds
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Chris Simmonds

Chris Simmonds is a software consultant and trainer living in southern England. He has almost two decades of experience in designing and building open-source embedded systems. He is the founder and chief consultant at 2net Ltd, which provides professional training and mentoring services in embedded Linux, Linux device drivers, and Android platform development. He has trained engineers at many of the biggest companies in the embedded world, including ARM, Qualcomm, Intel, Ericsson, and General Dynamics. He is a frequent presenter at open source and embedded conferences, including the Embedded Linux Conference and Embedded World.
Read more about Chris Simmonds

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Service supervision

Once we have created service directories with run scripts under /etc/sv and ensured that BusyBox init starts runsvdir, BusyBox runit handles all the rest. That includes starting, stopping, monitoring, and restarting all the services under its control. The runsvdir utility starts a runsv process for each service directory and restarts a runsv process if it terminates. Because run scripts run their respective daemons in the foreground, runsv expects run to block so that when run exits, runsv will restart it automatically.

Service auto-restart is desirable during system startup because run scripts can crash. This is especially true under BusyBox runit where services start virtually simultaneously instead of one after the other. For instance, a service may fail to start when a dependent service or essential system resource (such as a GPIO or device driver) is not yet available. In the next section, I will show you how to express dependencies between services so that...

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Mastering Embedded Linux Programming - Third Edition
Published in: May 2021Publisher: PacktISBN-13: 9781789530384

Authors (2)

author image
Frank Vasquez

Frank Vasquez is an independent software consultant specializing in consumer electronics. He has over a decade of experience designing and building embedded Linux systems. During that time, he has shipped numerous devices including a rackmount DSP audio server, a diver-held sonar camcorder, and a consumer IoT hotspot. Before his career as an embedded Linux engineer, Frank was a database kernel developer at IBM where he worked on DB2. He lives in Silicon Valley.
Read more about Frank Vasquez

author image
Chris Simmonds

Chris Simmonds is a software consultant and trainer living in southern England. He has almost two decades of experience in designing and building open-source embedded systems. He is the founder and chief consultant at 2net Ltd, which provides professional training and mentoring services in embedded Linux, Linux device drivers, and Android platform development. He has trained engineers at many of the biggest companies in the embedded world, including ARM, Qualcomm, Intel, Ericsson, and General Dynamics. He is a frequent presenter at open source and embedded conferences, including the Embedded Linux Conference and Embedded World.
Read more about Chris Simmonds