Raspberry Pi_Eng_14.1.1 Device Type and “/dev” Directory


Published Book on Amazon


All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 1
All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 2


출판된 한글판 도서


최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (상)
최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (하)


Original Book Contents


14.1   Device Overview

 

14.1.1  Device Type and "/dev" Directory

 

In the devices used in Linux, there are character device such as keyboards, block device such as disk, and network device such as Ethernet.

 

Once installed, character and block devices are registered in "/dev" directory as if they were one file, and they support access like normal files. On the other hand, for the network device, only the devices found in the system kernel initialization process is registered as a device, and is not registered as a file in "/dev" directory.

 

Typically, character devices or block devices have special device files even if they do not exist. This is why there are a lot of device files in the "/dev" directory even though there are not many devices in the actual system. However, the network device file is created only if the device actually exists.