A link creates a reference to a file or a folder. Symbolic links are used in Linux for managing and collating files.
In this guide, learn how to use the
ln command to create symbolic links in Linux.
- A system running Linux
- Access to a terminal window / command line (Activities > Search > type Terminal)
- (optional) A user account with sudo or root privileges (needed to access certain protected files and directories)
Ln Command to Create Symbolic Links
To use the
ln command, open a terminal window and enter the command with the following format:
ln [-sf] [source] [destination]
- By default, the
lncommand creates a hard link.
- Use the
-soption to create a soft (symbolic) link.
-foption will force the command to overwrite a file that already exists.
- Source is the file or directory being linked to.
- Destination is the location to save the link – if this is left blank, the symlink is stored in the current working directory.
For example, create a symbolic link with:
ln -s test_file.txt link_file.txt
This creates a symbolic link (link_file.txt) that points to the test_file.txt.
To verify whether the symlink has been created, use the ls command:
ls -l link_file.txt
Create a Symbolic Link to Linux Directory
A symbolic link can refer to a directory. To create a symbolic link to a directory in Linux:
ln -s /mnt/external_drive/stock_photos ~/stock_photos
This example creates a symbolic link named stock_photos in the home (~/) directory. The link refers to the stock_photos directory on an external_drive.
Note: If the system has a connection to another computer, such as a corporate network or a remote server, symlinks can be linked to resources on those remote systems.
Force Overwrite Symbolic Links
You might receive an error message as displayed in the image below:
The error message means that there’s already a file in the destination named link_file.txt. Use the
-f option to force the system to overwrite the destination link:
ln -sf test_file.txt link_file.txt
Note: Using the
-f option will permanently delete the existing file.
Deleting or Removing Links
If the original file is moved, deleted, or becomes unavailable (such as a server going offline), the link will be unusable. To remove a symbolic link, use either the
rm (remove) or
rm link_file.txt unlink link_file.txt
Soft Links vs Hard Links
ln command can be used to create two different kinds of links:
- Soft links
- Hard links
Soft (Symbolic) Links
A soft link, sometimes called a symbolic link or symlink, points to the location or path of the original file. It works like a hyperlink on the internet.
Here are a few important aspects of a soft link:
- If the symbolic link file is deleted, the original data remains.
- If the original file is moved or deleted, the symbolic link won’t work.
- A soft link can refer to a file on a different file system.
- Soft links are often used to quickly access a frequently-used file without typing the whole location.
When a file is stored on a hard drive, several things happen:
- The data is physically written to the disk.
- A reference file, calledinode, is created to point to the location of the data.
- A filename is created to refer to the inode data.
A hard link works by creating another filename that refers to the inode data of the original file. In practice, this is similar to creating a copy of the file.
Here are a few important aspects of hard links:
- If the original file is deleted, the file data can still be accessed through other hard links.
- If the original file is moved, hard links still work.
- A hard link can only refer to a file on the same file system.
- The inode and file data are permanently deleted when the number of hard links is zero.
You should now have a solid understanding of hard and symbolic (soft) links, and how to work with them. Use the
ln command to create links and verify using the