How to Change File Owner and Group in Linux

The chown command in Linux changes the ownership of files and directories. It’s essential for managing permissions, especially in multi-user environments or when transferring files between users. Below are practical examples to master chown:

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Change Ownership of a File

chown user1 file.txt  

Changes the owner of file.txt to user1.

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Change Ownership of a Directory

chown user1 /path/to/directory  

Changes the owner of the directory to user1.

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Change Ownership and Group Simultaneously

chown user1:group1 file.txt  

• Sets the owner to user1 and the group to group1.

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Change Group Ownership Only

chown :group1 file.txt  

Changes the group of file.txt to group1 (owner remains unchanged).

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Recursively Change Ownership of a Directory

chown -R user1 /path/to/directory  

• -R: Recursively changes ownership for all files and subdirectories.

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Change Ownership Using a Reference File

chown --reference=ref_file.txt target_file.txt  

Sets the ownership of target_file.txt to match ref_file.txt.

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Change Ownership for Symbolic Links

chown -h user1 symlink  

• -h: Changes ownership of the symbolic link itself, not the target file.

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Change Ownership and Suppress Errors

chown -f user1 file.txt  

• -f: Suppresses error messages (e.g., for inaccessible files).

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Change Ownership with Verbose Output

chown -v user1 file.txt  

• -v: Displays a message for each file processed.

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Change Ownership for All Files in a Directory

chown user1 *  

Changes ownership of all files in the current directory to user1.

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Change Ownership for Specific File Types

chown user1 *.txt  

Changes ownership of all .txt files in the current directory.

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Change Ownership and Preserve Root

chown --preserve-root -R user1 /  

• --preserve-root: Prevents recursive ownership changes on the root directory.

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Change Ownership for a Specific User and Group by UID/GID

chown 1001:1002 file.txt  

• 1001: User ID (UID).
• 1002: Group ID (GID).

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Change Ownership for Files Matching a Pattern

find /path/to/dir -name "*.log" -exec chown user1 {} \;  

• find: Locates .log files and changes their ownership to user1.

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Key Notes:

• Permissions: Only the root user or the file owner can change ownership.
• Recursive Changes: Use -R carefully to avoid unintended ownership changes.
• Symbolic Links: Use -h to modify the link itself, not the target.