


What is the command to modify file permissions in Linux?
The Linux command to modify file permissions is chmod. The basic syntax of the command is: 1. u, indicates user permissions; 2. g, indicates group permissions; 3. o, indicates other user permissions; 4. a, indicates all user permissions.
The operating environment of this tutorial: windows10 system, linux6.4.3 version, DELL G3 computer.
In Linux systems, the command to modify file permissions is chmod. With this command, users can change the permissions of a file or directory, including read, write, and execute.
The basic syntax of the command is:
chmod [permission option] [permission mode] [file name]
Among them, the permission option can be:
- u: Indicates user permissions
- g: Indicates group permissions
- o: Indicates other user permissions
- a: Indicates all users Permission
Permission mode can be:
-:Add permission
--:Remove permission
-=:Only Set the specified permissions
The permission mode can be the following:
- r: read permission
- w: write permission
- x: Execution permissions
For example, here are some specific command examples:
1. Add read-write execution permissions to the file owner:
chmod u rwx file.txt
2. Add read and execute permissions to group members:
chmod g rx file.txt
3. Remove write permissions for other users:
chmod o-w file.txt
4. Set read-only permissions to all users at the same time:
chmod a=r file.txt
5. Yes Represent permissions in numerical form, as follows:
chmod 755 file.txt
This will set read, write and execute permissions for the file owner, group members and other users can only Read and execute files.
It should be noted that modifying file permissions requires specific permissions. Only the owner of the file or a user with superuser permissions can modify the permissions of the file.
The above is the detailed content of What is the command to modify file permissions in Linux?. For more information, please follow other related articles on the PHP Chinese website!

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