navigation issue

Volcano · 04-26-2015, 02:54 AM

I am confused with the navigation in linux.

what does navigation /../demo will mean ?

does it mean we go to / first , then which path ?

veerain · 04-26-2015, 03:19 AM

'.' is current directory. '..' is parent directory of current directory.

But in this case '/../demo' there is no parent directory beyond the root directory '/'.

So this actually turns into '/demo'.

Volcano · 04-26-2015, 03:56 AM

Does ../ and /.. are same thing ? I am confused with the ordering of '..' to find its parent

Please guide.

veerain · 04-26-2015, 04:08 AM

If '/' comes first then it means the top most directory starts from / (root of filesystem).

E.g. a directory '/usr/bin' and you are in /usr/bin by 'cd /usr/bin'.

Now 'ls ../' or 'ls ../sbin' shows files in /usr in former and /usr/sbin in latter.

Again when your in /usr/bin and run 'ls -l /..' shows files in / directory (root).

unSpawn · 04-26-2015, 04:43 AM

...additionally

Quote:

Originally Posted by Volcano

Does ../ and /.. are same thing ? I am confused with the ordering of '..' to find its parent

try these commands to illustrate above replies:

Code:

]$ cd /var/tmp
]$ pwd
]$ readlink -f ../
]$ readlink -f /..

jpollard · 04-26-2015, 06:11 AM

Think of the directory tree as implemented by multiple links.

/ is the root of the tree.

the name of a directory is the link to the subtree.

.. is a backward link to one level higher in the tree.

. is for ease of use - it is a link to the current level of the tree (it makes it easy to do an ls without having to remember where you are in the tree).

frankbell · 04-26-2015, 09:09 PM

This article is a good primer on how to use the cd command, including

Code:

cd ..
cd -

and so on.

If you open a command prompt in Windows and run a dir command, you will also the

Code:

.
..

at the top of the file listing, just as you do when you run ls -a (list files -all, that is, including hidden files) in Linux.