December 2002
Intermediate to advanced
784 pages
27h 7m
English
Content preview from Understanding the Linux Kernel, Second EditionBecome 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.
Chapter 12. The Virtual Filesystem
One of Linux’s keys to success is its ability to coexist comfortably with other systems. You can transparently mount disks or partitions that host file formats used by Windows, other Unix systems, or even systems with tiny market shares like the Amiga. Linux manages to support multiple disk types in the same way other Unix variants do, through a concept called the Virtual Filesystem.
The idea behind the Virtual Filesystem is to put a wide range of information in the kernel to represent many different types of filesystems; there is a field or function to support each operation provided by any real filesystem supported by Linux. For each read, write, or other function called, the kernel substitutes the actual function that supports a native Linux filesystem, the NT filesystem, or whatever other filesystem the file is on.
This chapter discusses the aims, structure, and implementation of Linux’s Virtual Filesystem. It focuses on three of the five standard Unix file types—namely, regular files, directories, and symbolic links. Device files are covered in Chapter 13, while pipes are discussed in Chapter 19. To show how a real filesystem works, Chapter 17 covers the Second Extended Filesystem that appears on nearly all Linux systems.
The Role of the Virtual Filesystem (VFS)
The Virtual Filesystem (also known as Virtual Filesystem Switch or VFS) is a kernel software layer that handles all system calls related to a standard Unix filesystem. Its main strength ...
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.