How to change owner in linux

How to Change the Owner of Directory in Linux

Under a Linux file system, we have files, folders, and directories. A folder only contains files and a directory contains both folders and files. Each of these files, folders, and directories are associated with an owner, a group, and permission access rights.

This article guide will walk us through determining and changing the ownership of a directory on a Linux system.

Why Change Directory Ownership in Linux?

• You might need an already created directory to only be accessible by a specific user.
• In an organizational setting, when a user quits, changing the directory ownership to folders and data prevents/revokes the initial access privileges the user had.
• When working with scripts like Python or Bash scripts, their execution might need access to directory data and therefore a directory owner must be identified for these scripts to execute successfully.
• During file transfers between different Linux systems on a network, directory ownership needs to be changed with respect to the users involved.

Problem Statement

For this article, we need a preexisting directory with already set directory ownership. Consider the following directory whose ownership is revealed via the following commands.

$ ls -l LinuxShellTips_Files $ ls -l -d LinuxShellTips_Files

The first column reveals the associated permission access rights, the second column reveals the associated owner, and the third column shows the associated group.

In the above case, we have owner dnyce and group dnyce for LinuxShellTips_Files directory, its sub-directories and files.

Changing Directory Ownership in Linux

To meet this objective, we are going to borrow the effectiveness of the Linux chown command-line utility, which is part of the GNU Coreutils package and is primarily used to change the owner and group name of a targeted file.

The chown command reference syntax is as follows:

$ chown [OPTION]. [OWNER][:[GROUP]] FILE.

As per the above chown command syntax, we first need to identify the new owner and group name that will inherit the to-be vacated directory ownership.

To list all the active owners in your Linux system run the command:

To list all the active groups in your Linux system, run the command:

Alternatively, you could create a new user you wish to have the new ownership of the vacated directory.

$ sudo adduser tutor $ sudo adduser tutor sudo

Changing Directory Ownership

To change the ownership of our sample directory from owner dnyce to owner tutor, we will implement the following chown command.

$ sudo chown tutor LinuxShellTips_Files

Confirm that the directory ownership has changed:

$ ls -l -d LinuxShellTips_Files

To change both the user and group ownership of the directory to tutor, execute the command:

$ sudo chown tutor:tutor LinuxShellTips_Files

Changing Directory and Sub-directories Ownership

The sub-directories in the above parent directory have different ownership and to change their ownership to be the same as the parent directory, run:

$ sudo chown -R tutor:tutor LinuxShellTips_Files

Confirm if the ownership changes took place:

$ ls -l -d LinuxShellTips_Files $ ls -l LinuxShellTips_Files

We can now change the ownership of any directory on a Linux as a sudoer/root user.

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Chown Command: Change Owner of File in Linux

The chown command changes user ownership of a file, directory, or link in Linux. Every file is associated with an owning user or group. It is critical to configure file and folder permissions properly.

In this tutorial, learn how to use the Linux chown command with examples provided.

• Linux or UNIX-like system
• Access to a terminal/command line
• A user with sudo privileges to change the ownership. Remember to run the commands with sudo to execute them properly.

Linux Chown Command Syntax

The basic chown command syntax consists of a few segments. The help file shows the following format:

chown [OPTIONS] USER[:GROUP] FILE(s)

• [OPTIONS] – the command can be used with or without additional options.
• [USER] – the username or the numeric user ID of the new owner of a file.
• [:] – use the colon when changing a group of a file.
• [GROUP] – changing the group ownership of a file is optional.
• FILE – the target file.

Superuser permissions are necessary to execute the chown command.

In this guide, we tested the command examples with the chown version 8.28 in Ubuntu 18.04.2 LTS.

To check the chown version on your machine, enter:

The output will look similar to this:

How to Check Ownership of a File in Linux

First, you need to know the original file owner or group before making ownership changes using the chown command.

To check the group or ownership of Linux files and directories in the current location, run the following command:

An example output of the ls command looks like this:

How to Change the Owner of a File

Changing the owner of a file with chown requires you to specify the new owner and the file. The format of the command is:

The following command changes the ownership of a file sample from root to the user test:

Use the same format to change the ownership for both files and directories.

Change the Owner of a File With UID

Instead of a username, you can specify a user ID to change the ownership of a file.

Make sure there is no user with the same name as the numeric UID. If there is, the chown command gives priority to the username, not the UID.

Note: To check a user’s ID, run id -u USERNAME from the terminal.

Change Ownership of Multiple Linux Files

List the target file names after the new user to change the ownership for multiple files. Use single spaces between the file names.

In the following example, root will be the new owner of files sample2 and sample3.

chown root sample2 sample3

Combine file names and directory names to change their ownership with one command. For example:

Do not forget that the commands are case sensitive.

How to Change the Group of a File

With chown, you can change a group for a file or directory without changing the owning user. The result is the same as using the chgrp command.

Run the chown command using the colon and a group name:

The following example changes the group of the file sample3 from grouptest to group3.

List multiple names of files or directories to make bulk changes.

Change the Group of a File Using GID

Similar to UID, use a group ID (GID) instead of a group name to change the group of a file.

Change Owner and the Group

To assign a new owner of a file and change its group at the same time, run the chown command in this format:

chown NewUser:NewGroup FILE

Therefore, to set linuxuser as the new owner and group2 as the new group of the file sample2:

chown linuxuser:group3 sample3

Remember that there are no spaces before or after the colon.

Change Group to a Users Login Group

The chown command assigns the owner’s login group to the file when no group is specified.

To do so, define a new user followed by a colon, space, and the target file:

The following example changes the group ownership to the login group of linuxuser:

Transfer Ownership and Group Settings from One File to Another

Rather than changing the ownership to a specific user, you can use the owner and a group of a reference file.

Add the —reference option to the chown command to copy the settings from one file to another:

chown --reference=ReferenceFILE FILE

Remember to type in the names of the files correctly to avoid the error message:

Check Owner and Group Before Making Changes

The chown command —from option lets you verify the current owner and group and then apply changes.

The chown syntax for checking both the user and group looks like this:

chown --from=CurrentUser:CurrentGroup NewUser:NewGroup FILE

The example below shows we first verified the ownership and the group of the file sample3:

chown --from=root:group2 linuxuser:group3 sample3

Then chown changed the owner to linuxuser and the group to group3.

Check Owner Only

The option —from can be used to validate only the current user of a file.

chown --from=CurrentUser NewUser FILE

chown --from=root linuxuser sample3

Check Group Only

Similar to the previous section, you can validate only the group of a file using the option —from .

chown --from=:CurrentGroup :NewGroup FILE

Here is an example where we verified the current group before changing it:

chown --from=:group3 :group4 FILE

Remember to use the colon for both group names to avoid error messages.

How to Recursively Change File Ownership

The chown command allows changing the ownership of all files and subdirectories within a specified directory. Add the -R option to the command to do so:

chown -R NewUser:NewGroup DirNameOrPath

In the following example, we will recursively change the owner and the group for all files and directories in Dir1.

chown -R linuxuser:group3 Dir1

Chown Command and Symbolic Links

To change the owner of a symbolic link, use the -h option. Otherwise, the ownership of the linked file will be changed.

The following image shows how symbolic links behave when -h is omitted.

The owner and group of the symbolic link remain intact. Instead, the owner and the group of the file textfile changed.

To push the changes to the link, run the chown command with the -h flag:

chown -h NewUser:NewGroup SymbolicLink

In the following example, we changed the owner and group of a symbolic link.

Display Chown Command Process Details

By default, the terminal does not display the chown process information. To see what happens under the hood, use one of the two command line flags:

• The option –v produces the process details even when the ownership stays the same.
• The option –c displays the output information only when an owner or group of the target file changes.

For example, if we specify the current owner as a new owner of the file:

chown -v linuxuser sample2

The terminal produces the following output:

Switch from -v to -c and there will be no messages in this case. This happens because there are no owner or group changes.

The information is particularly useful with the recursive chown command:

In this example, the output lists all objects affected after running the command.

Suppress Chown Command Errors

To avoid seeing potential error messages when running the chown command, use the -f option:

The example below shows the error message for a non-existent file or directory:

Adding the -f flag suppresses most error messages. However, if you specify an invalid username, the error message appears:

Now you know how to use chown command in Linux to change a file’s user and/or group ownership.

Take extra caution when changing the group or ownership of a file or directories.

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