Using a Mac while being deeply involved in retro handhelds can often be a bit tricky. The guide on getting cover art is a diamond in the rough, offering a fast and simple way to grab artwork that outperforms many tools on other platforms.
On macOS, it’s not common to find many tools built specifically for this space. Even worse, the operating system itself can introduce processes that make things more complicated than they need to be. To make matters more confusing, macOS also hides certain files entirely.
What are AppleDoubles?
These are the dreaded ._ files you rarely see on macOS, but suddenly notice everywhere once you plug an SD card into another operating system. They feel like the devil, and the devil is in the details.
._ files are commonly called AppleDouble files. They store metadata created when files are modified on macOS. If you rename a file, move it, open it, copy it, or interact with it in almost any way, a ._ file can be created. These files mirror the original name exactly, just with ._ placed in front.
This makes their presence even more frustrating on other platforms. A folder with 100 games can suddenly appear as 200 items, with 100 useless files sitting right above the real ones. It clutters everything and gets in the way fast.
A lot of custom firmware options include tools to remove these files, but in my opinion, the better approach is to clean them off the SD card before putting it back into your retro handheld.
So let’s do that.
Do Your Deeds
This guide takes place after you’ve finished whatever you need to do on your SD card, not before. If you’re moving ROMs, do that first. If you’re reorganizing files, do that first. If you’re adding or editing anything, finish that first. Running this beforehand will not accomplish anything.
Open Up Terminal
It sounds intimidating, but it really isn’t. Trust me here.
Open Terminal, and within the window, type:
dot_clean
Do not run the command yet. Do not press Enter. Just type it, then press the spacebar. Nothing more.
Drag Your Drive
Open Finder. In the sidebar, you should see your Mac listed. This represents your system’s volumes. From there, locate your SD card.
Drag the SD card into the Terminal window right after dot_clean. You should now see the drive path appear after the command.
Optionally, you can add the -v flag at the end to have a command that looks something like this:
dot_clean /Volumes/SDCARDNAME -vThat -v means verbose, which means Terminal will show what’s happening in real time. You will see it merging ._ files back into their main files, and it should complete fairly quickly.
Note: If you see a forward slash in your drive name, that’s normal. It indicates a space in the name. If there’s a forward slash but no space in the drive name, then you’ve got bigger problems.
Run the Command
Enter Enter to run the command and wait a few seconds.
The speed of the command depends on the number of files, not their size. Ten thousand small files will take longer than a single large file. For reference, a ton of files can take a few minutes. One file will take less than a second.
Once it finishes, you’re done. You can safely eject the SD card from your Mac and put it back into your device and move on.
This process takes almost no time, and after doing it once, it becomes second nature. I personally run this command anytime I work with an SD card, whether it’s for retro handhelds, transferring photos, or anything else that moves between macOS and other systems.
As mentioned earlier, macOS rarely provides niche-focused tools for situations like this. It can be frustrating when the operating system itself introduces the problem. But in this case, there is at least a simple and effective way around it.
And that’s all it takes.
