How to differentiate a file from it's hard link ?

techie_san778 · 05-31-2016, 02:57 AM

Hello Friends,

It's known that a soft link can be distinguished by the 'l' in the o/p of
ls -l. But is there any way to distinguish a hard link from the original file ?

Regards

descendant_command · 05-31-2016, 03:17 AM

A hard link IS the original file.
(so are any other hardlinks pointing to the same inode).

techie_san778 · 05-31-2016, 03:25 AM

yes descendant_command, i actually meant the original file-name. Sorry for using the phrase "File". Let's say /abc/text is to be linked.
$ ln /abc/text /def/note
How to differentiate note from text ?

descendant_command · 05-31-2016, 03:33 AM

One has the name 'note', the other has the name'text' and they are both the same file.
What do you mean by "differentiate"?

pan64 · 05-31-2016, 03:48 AM

Quote:

Originally Posted by techie_san778

But is there any way to distinguish a hard link from the original file ?

No, you will not be able to tell which one was the "original" and which one is the link, because both of them are just entries in different directories pointing to the same content/file/inode. So there are no two files stored, just one, and that is the original one.

hydrurga · 05-31-2016, 03:54 AM

Quote:

Originally Posted by descendant_command

One has the name 'note', the other has the name'text' and they are both the same file.
What do you mean by "differentiate"?

I suspect that the OP considers one directory entry to be the "original" and one just to be a hard link to the original, and wants to differentiate between them.

In reality, of course, both directory entries point to the same inode ("file" so to speak), they are both hard links to the "original" file.

techie_san778 · 05-31-2016, 04:00 AM

@ descendant_command I meant that just as the 'l' in the o/p of ls -l means it is a soft link, is there any notation that denotes the file is a hard link ?

pan64 · 05-31-2016, 04:07 AM

by default every entry in a directory is a hardlink to an inode (especially a directory itself is a file, just handled differently)
using ls -l you will see a number after the access rights, that will tell you how many directory entries (filenames) uses the given inode:
ls -l /bin/bzip2 (if that works for you)
-rwxr-xr-x 3 root root 31152 okt 21 2013 bzip2

descendant_command · 05-31-2016, 04:11 AM

If you put an apple on a table, leave the room, and view it from outside the window and from outside the open door, which is the 'original' view of the apple?

pingu_penguin · 06-02-2016, 09:16 PM

There is no differentiation, a hard link is just another path pointing to the same data location on the disk.

If you are mean how to find out the file is hard linked , you can do :
#ls -li

Beryllos · 06-03-2016, 02:23 PM

Quote:

Originally Posted by techie_san778

Hello Friends,

It's known that a soft link can be distinguished by the 'l' in the o/p of
ls -l. But is there any way to distinguish a hard link from the original file ?

Regards

You could try hard-linking an existing file, and then try changing properties like permissions, mtime, or owner. When I tried this, the original and the link always showed the same.