Possible Duplicate:
Many directories have a “.d” suffix/extension. What does it mean?

Why do most of the folders in /etc/* end with *.d

I am just curious to know, why folders would have this ( extension? ).

enter image description here

  • You may find by using the search button that this question has already been answered here: askubuntu.com/questions/7648/… Edit: I searched for "config folder with ".d" suffix" – Tim Bielawa Feb 18 '11 at 8:16
  • 3
    Even if it's a duplicate, why downvote this question? It's a valid one. – Lekensteyn Feb 18 '11 at 9:03
  • 1
    Note, that there is no such thing "extension" in Unix (Linux included) - extensions are notion of CP/M and then DOS inherited this terminology but not UNIX systems -, dot is part of the file name, you can have even more, like "file.tar.gz" or things like "file........hello...this." etc. Though "." and ".." as names are special ones: this means the current and the parent directories. Also files (and directories) starting with "." are treated as "hidden" files, normally even "ls" does not show them only with using switch "-a". – LGB Feb 18 '11 at 11:11
  • 2
    @LGB Calling it extension (with a question mark) was also a part of the question; your comment could have been an answer, so my question still qualifies as a valid one. And I still don't understand why it was downvoted. – Gaurav Butola Feb 18 '11 at 13:10
  • @LGB It's still common, and valid, to refer to the last dot-delimited part(s) of a filename as an extension, when the function is to act as a technical type or purpose annotation for the file. For example, when a .NET/Mono executable on Windows ends in .exe that's called an extension (it's just part of the file name in NTFS, too!), and when that file is brought over to an Ubuntu system, it is correct to call the .exe suffix an extension here, too. Furthermore, .odt is an extension, .tar.gz and the final .gz can both be called extensions (and .tar.gz can exist on Windows too!). – Eliah Kagan Aug 14 '13 at 10:27

The .d denotes a directory containing configuration files, as opposed to a single config file.

This applies to other configuration directories under /etc such as /etc/apt.conf.d/, /etc/rc.d

Not the answer you're looking for? Browse other questions tagged or ask your own question.