Editing Root directory

{{Short description|First or top-most directory in a hierarchy}}
{{Other uses|Root (disambiguation)}}
[[File:OpenIndiana 2015 Console LS.png|thumb|View of the root directory in the [[OpenIndiana]] operating system]]

In a [[Computing|computer]] [[file system]], and primarily used in the [[Unix]] and [[Unix-like]] [[operating system]]s, the '''root directory''' is the first or top-most [[Directory (computing)|directory]] in a hierarchy.<ref name=":1">{{Cite web|url=https://techterms.com/definition/root_directory|title=Root Directory Definition|website=techterms.com|access-date=2020-03-14|archive-date=2020-10-26|archive-url=https://web.archive.org/web/20201026093038/https://techterms.com/definition/root_directory|url-status=live}}</ref>  It can be likened to the trunk of a [[Tree (data structure)|tree]], as the starting point where all branches originate from.  The '''root file system''' is the file system contained on the same [[Disk Partition Recovery|disk partition]] on which the root directory is located; it is the filesystem on top of which all other file systems are [[Mount (computing)|mounted]] as the system boots up.<ref>{{Cite web |url=http://www.linfo.org/root_filesystem.html |title=Root Filesystem Definition by The Linux Information Project |website=LInfo.org |access-date=2020-03-14 |archive-date=2021-07-10 |archive-url=https://web.archive.org/web/20210710200056/http://www.linfo.org/root_filesystem.html |url-status=live }}</ref>

==Unix-like systems==
Unix abstracts the nature of this tree hierarchy entirely and in Unix and Unix-like systems the root directory is denoted by the <code>/</code> (slash) sign. Though the root directory is conventionally referred to as <code>/</code>, the directory entry itself has no name{{snd}}  its path is the "empty" part before the initial directory separator character (<code>/</code>). All file system entries, including mounted file systems are "branches" of this root.<ref name=":1" />

===chroot===
In UNIX-like operating systems, each [[Process (computing)|process]] has its own idea of what the root directory is.  For most processes this is the same as the system's actual root directory, but it can be changed by calling the {{mono|[[chroot]]}} [[system call]].  This is typically done to create a secluded environment to run software that requires legacy libraries and sometimes to simplify software installation and debugging. Chroot is not meant to be used for enhanced security as the processes inside can break out.<ref>{{cite web |url=https://lwn.net/Articles/252794/ |title=What chroot() is really for |website=LWN.net |access-date=2014-02-12 |archive-date=2020-11-12 |archive-url=https://web.archive.org/web/20201112024828/https://lwn.net/Articles/252794/ |url-status=live }}</ref>

===Super-root===
{{See also|Newcastle Connection}}

Some Unix systems support a directory below the root directory. Normally, "/.." points back to the same [[inode]] as "/", however, under {{Interlanguage link multi|MUNIX|de}}, this can be changed to point to a super-root directory, where remote trees can be mounted.<ref name="Newcastle_1982">{{cite journal |title=The Newcastle Connection |author-last1=Brownbridge |author-first1=David R. |author-last2=Marshall |author-first2=Lindsay F. |author-last3=Randell |author-first3=Brian |author-link3=Brian Randell |journal=Software: Practice and Experience |volume=12 |year=1982 |doi=10.1002/spe.4380121206 |pages=1147–1162 |s2cid=1840438 |url=http://www.cs.ncl.ac.uk/publications/articles/papers/399.pdf |access-date=2016-08-16 |url-status=dead |archive-url=https://web.archive.org/web/20160816184205/http://www.cs.ncl.ac.uk/research/pubs/articles/papers/399.pdf |archive-date=2016-08-16 }}</ref><ref name="Callaghan_2000">{{cite book |author-last=Callaghan |author-first=Brent |title=NFS Illustrated |publisher=[[Addison Wesley]] |year=2000 |isbn=0-201-32570-5}}</ref>  If, for example, two workstations "pcs2a" and "pcs2b" were connected via "connectnodes" and "uunite" startup script, "/../pcs2b" could be used to access the root directory of "pcs2b" from "pcs2a".

==DOS/Windows systems==
Under [[DOS]], [[OS/2]], and [[Microsoft Windows]], each partition has a drive letter assignment (e.g. the C partition is labeled <code>C:\</code>) and there is no public root directory on it.

==Related uses==
On many [[Unix]]es, there is also a directory named {{mono|/root}} (pronounced "slash root").<ref name="LInfo 2007">{{cite web |url=http://www.linfo.org/root.html |title=Root Definition |website=LInfo.org |publisher=The Linux Information Project |date=2007-10-27 |access-date=2021-11-03 |archive-date=2021-05-08 |archive-url=https://web.archive.org/web/20210508093525/http://www.linfo.org/root.html |url-status=live }}</ref> This is the [[home directory]] of the 'root' [[superuser]].  On many [[Mac (computer)|Mac]] and [[iOS]] systems this superuser home directory is {{mono|/var/root}}.<ref name="LInfo 2007" />

A [[home page]]'s [[URL]] usually points to the root of the respective [[website]]'s [[domain name]].

==See also==
* [[Filesystem Hierarchy Standard]] (FHS)
* [[Parent directory]]
* [[Working directory]]

==References==
{{Reflist}}

{{Portal|Technology}}

[[Category:File system directories]]