What does /etc stands for in Linux/Unix ?

March 04, 2007
There is a discussion going on over at Slashdot regarding what /etc in Linux/Unix stands for. Is it an acronym or does it stand for 'et cetera' ? While the opinion is divided, the overwhelming thought is that it stands for et cetera. That is, what ever data which doesn't belong to other directories are put into /etc. Such as the 'motd' file (which stands for "Message Of The Day"). Many of us also look at /etc as a placeholder for the configuration files of programs which we run on our system.

Linux File System Hierarchy


If you look at the Linux file hierarchy, you find the following :

/bin - Common binaries

/sbin - Binaries used for system administration are placed here.

/boot - Static files of the boot loader. Usually it contain the Linux kernel, Grub boot loader files and so on.

/dev - Device files such as your CD drive, hard disk, and any other physical device.

In Linux/Unix, the common premise is that everything is a file.


/home - User HOME directories are found here. In unices like FreeBSD, the HOME directories are found in /usr/home. And in Solaris it is in /export. So quite a big difference here.

/lib - Essential shared libraries and kernel modules.

/mnt - Temporary mount point useful for when you insert your USB stick and it gets mounted under /mnt. Though in Ubuntu and the likes, it is usually mounted under /media.

/var - Variable data, such as logs, news, mail spool files and so on which is constantly being modified by various programs running on your system.

/tmp - Temporary files are placed here by default.

/usr - The secondary hierarchy which contain its own bin and sbin sub-directories.

/etc - Usually contain the configuration files for all the programs that run on your Linux/Unix system.

/opt - Third party application packages which does not conform to the standard Linux file hierarchy can be installed here.

/srv - Contains data for services provided by the system.

And of course there is the /proc directory which does not actually reside on the disk.

The file system hierarchy standard [FSHS] explains /etc as follows :

The /etc hierarchy contains configuration files. A "configuration file" is a local file used to control the operation of a program; it must be static and cannot be an executable binary.

It further goes on to say :

No binaries may be located under '/etc'. And the following directories, or symbolic links to directories are required in /etc:
  • opt Configuration for /opt
  • X11 Configuration for the X Window system (optional)
  • sgml Configuration for SGML (optional)
  • xml Configuration for XML (optional)

While this is the long and short of the matter, some believe that '/etc' is indeed an acronym and stands for "Editable Text Configuration". Oh well, the media is still not out with the verdict.

5 comments:

  • /etc = "Extended Tool Chest"

    OR

    "Extremely Terrible Cognomen" ;-)

    Source : Gnome Mailing List

  • /etc = every thing config

    :p

  • /etc = "Eat 'taters, commie!"

  • Kumaran

    /etc : Extended Table of Contents

  • Mohammed Q. Hussain

    Hello ...

    I have question about this point "And of course there is the /proc directory which does not actually reside on the disk."

    Do you mean the information in /proc isn't stored in hard disk? i think you mean these information stored in kernel structs, is this true?