48 lines
1.8 KiB
Markdown
48 lines
1.8 KiB
Markdown
---
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title: File Permissions
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---
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# File Permissions
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* In Linux each file and directory has three user based permission groups:
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**owner (u)** - This group of permissions apply only on owner of directory or file, and they do not impact the actions of other users.
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**group (g)** - This group of permissions apply only on group of user that are assigned to the directory or file, and they do not impact the actions of other users.
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**all users (o)** - This group of permissions apply to all users on the system.
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* In Linux each file and directory has three basic permission types:
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**read** - This permission allows user to read content of files.
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**write** - This permission allows user to write or modify the file or directory.
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**execute** - This permission allows user to execute a file or view the content of directory.
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* To view permission you can use some of content listing commands such as `ls -l`, `ll` and etc.
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Permissions are displayed as **_rwxrwxrwx**. Where _ means it is either directory marked as `drwxrwxrwx` or link marked as `lrwxrwxrwx`, first set of rwx are permissions for owner, second one are for group and the last set of rwx permissions are applied on all users.
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Usually each set of permissions has its value in integer. You can calculate each set value if you sum default values of each permission.
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**read (r)** = **4**
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**erite (w)** = **2**
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**execute (x)** = **1**
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This is important when you want to grant permissions to some type of user `owner`, `group`, `all users`. Granting permissions is usually done with command `chmod`.
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```
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chmod u=rwx,g=rx,o=r myfile
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```
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or equivalent
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```
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chmod 754 myfile
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```
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Example with no permission for groups
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```
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chmod 704 myfile
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```
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