lk/basics/soft_links.md
2024-08-07 18:03:14 +02:00

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---
title: "soft links"
tags: [ "basics", "links" ]
---
A soft link is a file which says how to go to another file.
When a program encounters a soft link, it will make a guess at whether it should ignore it, or try to get to that file.
To make a soft link to a file in the current directory, linking is easy:
```bash
fortune > $file_1
ln -s $file_1 $link_1
```
Now imagine your directory looks like this:
```
dir_0/
├── dir_1
│   └── file_1
├── dir_2
│   └── file_1
├── file_1
└── link_1
```
Inside `dir_1`, making a soft link to `dir_0/file_1` would mean putting the directions to that file:
```bash
cd dir_1
ln -s ../file_1 link_1
```
The real content of the file is just '`../file_1`, so making it from another directory would mean writing exactly the same address to that file:
```bash
ln -s ../file_1 dir_2/link_2
```
Both symlinks are identical, except for the name.
```
dir_0/
├── dir_1
│   ├── file_1
│   └── link_1 <-- This one points to ../file_1
├── dir_2
│   ├── file_1
│   └── link_2 <-- This one points to ../file_1 as well.
└── file_2
```
Since it's just an address, you can delete the original file, then make another.
```bash
rm file_1
ls -l dir_1/
fortune > file_1
cat dir_2/link_2
fortune | tee -a file_1
cat dir_1/link_1
```
Last, let's make a link from `dir_2/link_2` to `dir_1/file_1` (this will delete the old link):
```bash
ln -s -f ../dir_1/file_1 dir_2/link_2
cat dir_2/link_2
```