"Exporting" mp3 files - strange behavior

There's a Terminal command that will remove these files.

The command is dot_clean -m [directory].

Right before you eject a flash drive, go into Terminal and type dot_clean -m followed by a space. Then drag and drop the USB drive icon from the Finder into the Terminal window. (This is a shortcut for entering the proper Unix directory name of the flash drive, with all of the escape characters required for the command line.). Hit RETURN. Then Eject the flash drive from the Mac before the Finder gets the idea to write any more ._* files to it.

With a little work, you can probably set up an Automator actions or something like that so that you can just drag a USB flash drive's icon onto an automation script icon to clean it. There are other posts in these forums somewhere that describe how to do that.

If you're curious about dot_clean, you can type man dot_clean at the command line and you will get a description of what it does, and what command line arguments it takes. man is a standard Unix command to view the manual entries for command-line commands (including itself!).

It’s been a while since I did that, but I do remember having an app called “dot cleaner” or something similar that I had to use to remove all of the “._” files before the receiver was able to actually use the drive.

Search the Mac App Store.

They are extended attribute files that macOS creates. You cannot stop them from being created. However, you can remove them.

Here is an easy way to remove them from your flash drive(s):

https://www.youtube.com/watch?v=fVWJMdFeUbU

Just be very careful that you "cd" to the flash drive. ("cd"= change directory)

Don't accidentally apply the "rm" command to your internal disk. ("rm" = remove, and it is permanent removal)

And remove ONLY the "._" files

BlueHarvest

The most powerful way to keep your disks clean of macOS metadata.

http://www.zeroonetwenty.com/blueharvest/