File permissions change when transfering between external drives and laptop

I noticed a few years ago that when I transfer files back and forth between my laptop and my external drive all the files that I have transfered have changed permissions.

I format all my external drives as exFAT so I can use larger files.

Why does this happen?

Is there a better way to keep the file permissions intact when transfering files back and forth between external drives?

The test file: Fantastic Fungi (2019).mkv

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This is what the file permssions looks like before I transfer it to my external hard drive

ls -l

-rw-r–r-- 1 user user 577761580 May 2 2024 ‘Fantastic Fungi (2019).mkv’

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This is what the file permssions looks like after I transfer it back to my laptop

ls -l

-rwxr-xr-x 1 user user 577761580 May 2 2024 ‘Fantastic Fungi (2019).mkv’

When I right click file permissions dialogue box. The “Allow this file to run as a program” is ticked.

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The way have overcome this is to run a simple one liner to reset the permissions for directories and files.

Open a terminal in the directory of the folders and files you want to change

All directories will be 775. All files will be 664

find . -type d -exec chmod 0755 {} ;

find . -type f -exec chmod 0644 {} ;

Directory permission 0755 is similar to “drwxr-xr-x”

File permission 0644 is equal to “-rw-r–-r–-“.

-type d = directories

-type f = files

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