Finding your way around the Linux filesystem
Posted by Anonymous on Mon 26 Sep 2005 at 14:23
If you've ever been confused at all the directories present within your Linux system here is a quick overview of the directories in common use, and what they contain.
All of this information was condensed from the text in the output of the following command:
skx@home:~$ man 7 hier
If you have the manpages package installed (recommended) you can run it yourself.
This is the root directory. This is where the whole tree starts.
This directory contains executable programs which are needed in single user mode and to bring the system up or repair it.
Contains static files for the boot loader. This directory only holds the files which are needed during the boot process. The map installer and configuration files should go to /sbin and /etc.
Special or device files, which refer to physical devices. See "man 1 mknod" for details on creating new nodes.
Contains configuration files which are local to the machine. Some larger software packages, like X11, can have their own sub-directories below /etc. Site-wide configuration files may be placed here or in /usr/etc. Nevertheless, programs should always look for these files in /etc and you may have links for these files to /usr/etc.
Host-specific configuration files for add-on applications installed in /opt.
When a new user account is created, files from this directory are usually copied into the user's home directory.
Configuration files for the X11 window system (optional).
On machines with home directories for users, these are usually beneath this directory, directly or not. The structure of this directory depends on local administration decisions.
This directory should hold those shared libraries that are nec- essary to boot the system and to run the commands in the root filesystem.
This directory contains mount points for temporarily mounted filesystems
This directory should contain add-on packages that contain static files.
This is a mount point for the proc filesystem, which provides information about running processes and the kernel. This pseudo-file system is described in more detail in "man 5 proc".
This directory is usually the home directory for the root user
Like /bin, this directory holds commands needed to boot the system, but which are usually not executed by normal users.
This directory contains temporary files which may be deleted with no notice, such as by a regular job or at system boot up. (Debian does clean /tmp as part of the boot process - unless you prevent it.
This directory is usually mounted from a separate partition. It should hold only sharable, read-only data, so that it can be mounted by various machines running Linux.
This is the primary directory for executable programs. Most programs executed by normal users which are not needed for booting or for repairing the system and which are not installed locally should be placed in this directory.
The traditional place to look for X11 executables; on Linux, it usually is a symbolic link to /usr/X11R6/bin.
Binaries for games and educational programs (optional).
Include files for the C compiler.
Include files to use with the GNU C++ compiler.
Object libraries, including dynamic libraries, plus some executables which usually are not invoked directly. More complicated programs may have whole subdirectories there.
This is where programs which are local to the site typically go.
Binaries for programs local to the site.
Locally installed programs for system administration.
Source code for locally installed software.
This directory contains program binaries for system administration which are not essential for the boot process, for mounting /usr, or for system repair.
This directory contains subdirectories with specific application data, that can be shared among different architectures of the same OS.
Source files for different parts of the system, included with some packages for reference purposes. Don't work here with your own projects, as files below /usr should be read-only except when installing software.
This was the traditional place for the kernel source. Some distributions put here the source for the default kernel they ship. You should probably use another directory when building your own kernel.
This directory contains files which may change in size, such as spool and log files.
Data cached for programs.
Variable state information for programs.
Lock files are placed in this directory.
Miscellaneous log files.
Run-time variable files, like files holding process identifiers (PIDs) and logged user information (utmp). Files in this directory are usually cleared when the system boots.
Spooled (or queued) files for various programs.
Spooled jobs for at.
Spooled jobs for cron. See command scheduling with cron for more details.