Page 45 - DCAP104_EXPOSURE_TO_COMPUTER_DISCPLINES

Exposure to Computer Disciplines

Notes
Figure 3.3

bin etc Dev Home proc cdrom usr var

bash passwd pts Kaharris 1 assign 1 include log

2 51081 status studio.h wtmp

notes
assign 1

The Unix File System is much more complicated than it appears:

• The root directory is located on hard disk whose file system is organized using a Linux
file system organization, ext2.

• There is a CD-ROM in the cd drive whose file system is organized using High-SierraFile
Systems, HSFS.

• The directory /proc does not even exist on a device. The files are not storage locations
of data yet they appear to have content: cat /proc/1/status or cat /proc/mounts.

• The “files” in /dev are actually physical devices. For example, /dev/pts/2 is your
terminal device, /dev/mouse is my mouse and /dev/lp0 is a printer.

The File System: Layers of Abstraction

Figure 3.4

Block Physical Devices

Device Drivers

Individual File Systems

Virtual File System

Program

User

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