Symlink is a file that points to the original file or directory path.

By using symlink, you can avoid duplicating data, organize files efficiently, and save disk space.

Example

Hypothetical File Structure

Suppose you have the following directory strucrture on your computer:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11

/home/
│
├── user/
│   ├── documents/
│   │   ├── report.txt
│   │   └── notes.txt
│   │
│   └── projects/
│       └── project1/
│           ├── data.csv
│           └── analysis.py

Let’s say you frequently need to access data.csv from the projects/project1/ directory while working in the documents directory. To make this easier, you can create a symlink in documents folder that points directly to data.csv. From your terminal, you would first navigate to the documents directory:

First, you should go to the directory (documents) that you want to link the targeted file (data.csv).

1

cd /home/user/documents

Then, you can createw the symlink by using the following command:

1

ln -s ../projects/project1/data.csv data_link.csv

Now your directory structure looks like this:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17

/home/
│
├── user/
│   ├── documents/
│   │   ├── report.txt
│   │   ├── notes.txt
│   │   └── data_link.csv -> ../projects/project1/data.csv
│   │
│   ├── photos/
│   │   └── vacation/
│   │       ├── img001.jpg
│   │       └── img002.jpg
│   │
│   └── projects/
│       └── project1/
│           ├── data.csv
│           └── analysis.py

The symlink data_link.csv in the documents directory doesn’t contain the data itself but is merely a reference to data.csv located in /home/user/projects/project1/. When you access data_link.csv, the operating system redirects you to the original data.csv file. If data.csv is updated, those changes will appear when accessing it through data_link.csv as well.

If you run a command to view the contents of data_link.csv, such as:

1

cat data_link.csv

This will display the contents of data.csv, because the symlink directs to that file.

What Happens When the Linked File is Deleted?

When the target of symbolic link (symlink) is deleted, the symlink becomes whawt is commonly referred to as a “dangling link” or “broken link”. This means that the symlink still exists but points to a non-existent file or directory.

To prevent issues related to danglink symlinks, especially in scripts or automated systems, it’s good practice to check that a symlink’s target exits before accessing it.

If you want to see details about files and symlinks in a directory, you could use ls -l like this:

1

ls -l /path/to/directory