Linux - NewbieThis Linux forum is for members that are new to Linux.
Just starting out and have a question?
If it is not in the man pages or the how-to's this is the place!
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Introduction to Linux - A Hands on Guide
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
Click Here to receive this Complete Guide absolutely free.
they're all directories containing a virtual(pseudo)-filesystem, they don't use disk space and use a little bit of ram, so, they don't need to have a device associated, another way is 'proc /proc proc defaults 0 0' but it's the same
Last edited by gengisdave; 01-09-2014 at 09:32 AM.
The "none" is just a place holder required for the syntax of the fstab file.
For filesystems that don't use a device, you can actually put anything in there you want. "none" satisfies the syntax, and if at some time in the future change the fstab file such that a real device is needed, it will immediately report the error, and identify that "device doesn't exist". Putting anything else in there could just cause confusion.
This means that when no real device name is declared than the "device" would be considered the RAM ?
Not exactly... it is both yes and no. The filesystem used MAY be ram based... Now system tables are represented as a filesystem (like the /proc, /sys filesystems), and that is in memory, but is not anything like a device or even ramdisk. But like some FUSE filesystems, it just means there is no dedicated device. FUSE interprets file access (via the fstab) into whatever the user definition is. If there is a device assocated with it, it would be specified as configuration to the FUSE implementation, and that can be a database system (MySQLfs is one) or some other representation.
Modern Linux distributions include a /sys directory as a virtual filesystem (sysfs, comparable to /proc, which is a procfs), which stores and allows modification of the devices connected to the system, whereas many traditional UNIX and Unix-like operating systems use /sys as a symbolic link to the kernel source tree. -> now I understand /sys
The summary is that (for a begginer only):
the paths /proc, /sys, /dev/pts are not mount points for something existing on a HDD but locations where the OS is putting runtime information. That's why they have none - because is the OS's job to know who is the "device" where to store these runtime information.