Slackware Linux Basics - Huihoo

Chapter 4. General concepts 17
administrator to connect a device to any directory in the filesystem structure. This process is named mounting. For
example, one could mount the CD-ROM drive to the /cdrom directory. If the mount is correct, the files on the CD-
ROM can be accessed through this directory. The mounting process is described in detail in Section 8.8, “Mounting
filesystems”.
Common directories
The Filesystem Hierarchy Standard Group has attempted to create a standard that describes which directories should be
available on a GNU/Linux system. Currently, most major distributions use the Filesystem Hierarchy Standard (FHS)
as a guideline. This section describes some mandatory directories on GNU/Linux systems.
Please note that GNU/Linux does not have a separate directory for each application (like Windows). Instead, files are
ordered by function and type. For example, the binaries for most common user programs are stored in /usr/bin,
and their libraries in /usr/lib. This is a short overview of the important directories on a Slackware Linux system:
• /bin: essential user binaries that should still be available in case the /usr is not mounted.
• /dev: device files. These are special files used to access certain devices.
• /etc: the /etc directory contains all important configuration files.
• /home: contains home directories for individual users.
• /lib: essential system libraries (like glibc), and kernel modules.
• /root: home directory for the root user.
• /sbin: essential binaries that are used for system administration.
• /tmp: a world-writable directory for temporary files.
• /usr/bin: stores the majority of the user binaries.
• /usr/lib: libraries that are not essential for the system to boot.
• /usr/sbin: nonessential system administration binaries.
• /var: variable data files, like logs.
4.3. Devices
Introduction
In GNU/Linux virtually everything is represented as a file, including devices. Every GNU/Linux system has a directory
with special files, named /dev. Each file in the /dev directory represents a device or pseudo-device. A device file
has two special numbers associated with it, the major and the minor device number. The kernel knows which device
a device file represents by these device numbers. The following example shows the device numbers for the /dev/
zero device file:
$ file /dev/zero
/dev/zero: character special (1/5)
The file command can be used to determine the type of a file. This particular file is recognized as a device file that
has 1 as the major device number, and 5 as the minor device number.
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