68 lines
1.5 KiB
Markdown
68 lines
1.5 KiB
Markdown
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# The `chmod` command
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The `chmod` command allows you to change the permissions on a file using either a symbolic or numeric mode or a reference file.
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### Examples:
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1. Change the permission of a file using symbolic mode:
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```
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chmod u=rwx,g=rx,o=r myfile
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```
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The command above means :
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- user can read, write, execute `myfile`
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- group can read, execute `myfile`
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- other can read `myfile`
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2. Change the permission of a file using numeric mode
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```
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chmod 754 myfile user:group file.txt
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```
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The command above means :
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- user can read, write, execute `myfile`
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- group can read, execute `myfile`
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- other can read `myfile`
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3. Change the permission of a folder recursively
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```
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chmod -R 754 folder
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```
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### Syntax:
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```
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chmod [OPTIONS] MODE FILE(s)
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```
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- `[OPTIONS]` :
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`-R`: recursive, mean all file inside directory
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- `MODE`: different way to set permissions:
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- **Symbolic mode explained**
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- u: user
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- g: group
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- o: other
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- =: set the permission
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- r: read
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- w: write
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- x: execute
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- example `u=rwx` means user can read write and execute
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- **Numeric mode explained**:
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The **numeric mode** is based off of a binary representation of the permissions for user, group, and others, for more information please look at this [explanation](https://www.digitalocean.com/community/tutorials/linux-permissions-basics-and-how-to-use-umask-on-a-vps#types-of-permissions) from Digital Ocean's community section:
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- 4 stands for "read",
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- 2 stands for "write",
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- 1 stands for "execute", and
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- 0 stands for "no permission."
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- example 7 mean read + write + execute
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