Hard and Symbolic links on Linux

A link in UNIX is a pointer to a file. Like pointers in any programming languages, links in UNIX are pointers pointing to a file or a directory. Creating links is a kind of shortcuts to access a file. Links allow more than one file name to refer to the same file, elsewhere.

There are two types of links :

  1. Hard Links

These links behave differently when the source of the link (what is being linked to) is moved or removed. Symbolic links are not updated (they merely contain a string which is the pathname of its target); hard links always refer to the source, even if moved or removed.

For example, if we have a file a.txt. If we create a hard link to the file and then delete the file, we can still access the file using hard link. But if we create a soft link of the file and then delete the file, we can’t access the file through soft link and soft link becomes dangling. Basically hard link increases reference count of a location while soft links work as a shortcut (like in Windows)

1. Hard Links

  • Each hard linked file is assigned the same Inode value as the original, therefore they reference the same physical file location. Hard links more flexible and remain linked even if the original or linked files are moved throughout the file system, although hard links are unable to cross different file systems.
$ ln  [original filename] [link name]

2. Soft Links

  • A soft link is similar to the file shortcut feature which is used in Windows Operating systems. Each soft linked file contains a separate Inode value that points to the original file. As similar to hard links, any changes to the data in either file is reflected in the other. Soft links can be linked across different file systems, although if the original file is deleted or moved, the soft linked file will not work correctly (called hanging link).
$ ln  -s [original filename] [link name]

Difference between the two

  • Hard links cannot link to directories / folders / folders.

Soft or symbolic links are similar to Hard Link. They allow you to associate multiple files to a specific file, but also allow you to:

  • Create links between directories / folders / folders.

These links behave differently when the source of the link is moved or removed.

  • Symbolic links are not updated.

--

--

Developing in Holberton School

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store