How to Manage File Extensions with Cinnamon Desktop on Linux Mint

Linux Mint is one of the most popular Linux distributions, known for its user-friendly interface and reliability. The Cinnamon desktop environment, which is the default for Linux Mint, provides an intuitive way to manage files, including their extensions. File extensions help the operating system and applications recognize file types and determine how to open or execute them. In this guide, we’ll explore how to manage file extensions in Linux Mint using the Cinnamon desktop environment.

What Are File Extensions and Why Do They Matter?

A file extension is a set of characters at the end of a filename, typically after a period (.). It identifies the file format and determines which application should be used to open it. Some common file extensions include:

• .txt – Text file
• .jpg – JPEG image
• .png – PNG image
• .mp3 – Audio file
• .mp4 – Video file
• .pdf – Portable Document Format

In Linux Mint, file extensions are important, but the system also relies on MIME types and file headers to determine file types, rather than just the extension.

1. Viewing File Extensions in Cinnamon Desktop

By default, Cinnamon does not always show file extensions in the File Manager (Nemo). To ensure you can see file extensions:

1. Open Nemo (File Manager): Click on the Files icon from the taskbar or press Super + E (Windows key + E).
2. Enable Extensions:
   • Click on View in the menu bar.
   • Check Show Hidden Files (or press Ctrl + H).
   • Make sure Show Text in Icons is enabled so filenames (including extensions) are fully visible.

If file extensions are still hidden, ensure that Preferences > Display has “Show file extensions” enabled.

2. Changing File Associations (Default Applications)

Sometimes, you may want a particular file type to open with a different application. Here’s how to change the default application for a specific file type:

1. Right-click the file and select Properties.
2. Go to the Open With tab.
3. Select the application you want to use.
4. Click Set as Default to make it the new default for all files with that extension.

Alternatively, if you want more control over MIME types, you can use the xdg-mime command:

xdg-mime default vlc.desktop video/mp4

This command sets VLC Media Player as the default application for MP4 video files.

3. Renaming File Extensions

Sometimes, you may need to change a file’s extension manually. You can do this in several ways:

Using the File Manager (Nemo)

1. Locate the file whose extension you want to change.
2. Right-click and choose Rename.
3. Modify the extension, e.g., change file.txt to file.md.
4. Press Enter, and confirm if prompted.

Using the Terminal

For renaming files via the command line, use the mv command:

mv oldfile.txt newfile.md

If you want to change the extensions of multiple files in a directory, use:

rename 's/\.txt$/\.md/' *.txt

This changes all .txt files in the current directory to .md.

4. Handling Unknown or Misidentified File Extensions

Sometimes, a file may not have an extension or may be misidentified. To determine its actual type:

1. Use the file command:

   file unknownfile
   

   Example output:

   unknownfile: PNG image data, 800 x 600, 8-bit/color RGBA, non-interlaced
   

2. Check MIME type:

   xdg-mime query filetype unknownfile
   

If the file is wrongly identified, you can manually rename it with the appropriate extension.

5. Forcing Files to Open with a Specific Application

If a file is not opening in the desired application, you can explicitly run it with the preferred software:

xdg-open file.pdf

or

libreoffice file.docx

For graphical use, right-click the file, select Open With, and choose the desired application.

6. Creating Custom File Associations

If you have a file type not associated with any application, you can manually set its default program:

1. Open the MIME database file:

   nano ~/.config/mimeapps.list
   

2. Locate the MIME type you want to modify, e.g.,

   text/plain=gedit.desktop
   

   Change gedit.desktop to your preferred text editor, such as xed.desktop for Linux Mint’s default text editor.

3. Save and close the file (Ctrl + X, then Y and Enter).

7. Managing File Extensions Using GUI Tools

Besides using the terminal, Linux Mint provides GUI tools to manage file types:

• Nemo’s Properties Menu: Right-click a file and check its properties.
• MIME Type Editor (mimetype-editor): Allows managing file associations.
• Menulibre (sudo apt install menulibre): Useful for editing desktop entries.

8. Dealing with Executable Extensions (.sh, .desktop, .AppImage)

Executable files like .sh (shell scripts) and .desktop files require execution permissions:

1. Grant Execution Permission:

   chmod +x script.sh
   

2. Run the Script:

   ./script.sh
   

3. For .desktop Files:

   • Right-click the .desktop file > Properties > Permissions.
   • Enable Allow executing file as program.

For AppImage files:

chmod +x appimage.AppImage
./appimage.AppImage

9. Removing or Adding File Extensions in Bulk

To remove file extensions:

rename 's/\.bak$//' *.bak

To add .txt extensions to all files:

rename 's/$/\.txt/' *

10. Using File Managers Other than Nemo

If you use another file manager like Thunar or Dolphin, the process of managing file extensions is similar, but the settings may be in different locations.

Conclusion

Managing file extensions in Linux Mint with Cinnamon is straightforward, thanks to its user-friendly interface and powerful terminal commands. Whether you’re renaming files, changing default applications, or dealing with missing extensions, Cinnamon provides multiple ways to handle file extensions efficiently. By following this guide, you can take full control over file types and their associated applications on your Linux Mint system.

Frequently Asked Questions (FAQs)

1. Can I hide file extensions in Linux Mint?

Yes, you can hide file extensions by disabling “Show file extensions” in Nemo’s preferences, but it’s generally not recommended.

2. Why can’t I rename a file extension?

Some files may have restricted permissions. Try using sudo mv filename.old filename.new in the terminal.

3. How do I reset file associations in Cinnamon?

Delete the MIME settings:

rm ~/.config/mimeapps.list

Then log out and log back in.

4. Are file extensions case-sensitive in Linux?

Yes, file.TXT and file.txt are treated as different files.

5. Can I change multiple file extensions at once?

Yes, using the rename command:

rename 's/\.oldext$/\.newext/' *.oldext

6. What if a file has no extension?

You can determine its type using file unknownfile and manually rename it if necessary.

By mastering these file management techniques, you can improve your workflow and make better use of Linux Mint’s powerful file-handling capabilities! 🚀