75 lines
1.5 KiB
Markdown
75 lines
1.5 KiB
Markdown
---
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title: soft links
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tags:
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- basics
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- links
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---
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A soft link is a file which says how to go to another file.
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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.
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To make a soft link to a file in the current directory, linking is easy:
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```sh
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fortune > $file_1
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ln -s $file_1 $link_1
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```
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Now imagine your directory looks like this:
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```
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dir_0/
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├── dir_1
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│ └── file_1
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├── dir_2
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│ └── file_1
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├── file_1
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└── link_1
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```
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Inside `dir_1`, making a soft link to `dir_0/file_1` would mean putting the directions to that file:
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```sh
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cd dir_1
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ln -s ../file_1 link_1
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```
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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:
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```sh
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ln -s ../file_1 dir_2/link_2
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```
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Both symlinks are identical, except for the name.
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```
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dir_0/
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├── dir_1
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│ ├── file_1
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│ └── link_1 <-- This one points to ../file_1
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├── dir_2
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│ ├── file_1
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│ └── link_2 <-- This one points to ../file_1 as well.
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└── file_2
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```
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Since it's just an address, you can delete the original file, then make another.
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```sh
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rm file_1
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ls -l dir_1/
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fortune > file_1
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cat dir_2/link_2
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fortune | tee -a file_1
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cat dir_1/link_1
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```
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Last, let's make a link from `dir_2/link_2` to `dir_1/file_1` (this will delete the old link):
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```sh
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ln -s -f ../dir_1/file_1 dir_2/link_2
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cat dir_2/link_2
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```
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