How do I delete files only visible to other PCs?

Question

Level 6

17,017 points

How do I delete files only visible to other PCs?

When I try to copy image files on to a flash drive for my TV to display, there is an additional invisible file for each image. This extra file confuses the TV as it tries to display these non-image jpg files. The same happens when I copy MP3 files for the audio player in my car (or another one in a rack at work) -- it tries to play these extra files and every thing comes to a halt.

When I use Terminal to display invisible files, the usualtrash and other hidden files show up, but these "resource fork" like files associated with the images don't show. A file name might be "._012_12-2.jpg" which is associated with the un-creatively named image "012_12.jpg"

I think that a while back I used a Windows computer to erase these files. Surely that's not the only way! How do you get rid of these files so that TVs and MP3 players don't choke on a flash drive?

Posted on Jul 24, 2015 10:41 AM

Reply

Answer 1

Top-ranking reply

Kurt Lang

Level 9

68,478 points

Jul 24, 2015 10:58 AM in response to Richard.Taylor

Any file that begins with ._ isn't an image. When you copy files from a Mac to a drive formatted as FAT32 or ExFAT, the Mac OS creates two files. One is the data, and the other is the resource fork information written as a separate file. It has to do this since the drive formats mentioned don't support a twin fork file system, so OS X has to save the resource fork data a different way. You don't see them from your Mac since anything that begins with a period is automatically hidden.

So if you copied a file name hillside.jpg to a FAT32 or ExFAT drive, OS X will create these two files:

hillside.jpg (the actual image)

._hillside.jpg (the Mac resource fork data)

A free and pretty easy way to remove the ._ files is to use Terminal. I'm going to assume a USB drive for the following.

Plug in your flash drive so it appears on the Mac desktop. Open Terminal and enter:

dot_clean -m

Enter a space after the -m . Then drag and drop the icon of your flash drive into the Terminal window. It will fill in the path of the drive. Press Enter. All ._ files will be removed from that volume.

Be aware it will remove all ._ files. Including those that actually may be data, such as the resource fork for Mac Type 1 PostScript fonts and Mac legacy TrueType fonts. If you remove the ._ files for those, the fonts will be destroyed (no data left).

Reply

Answer 2

Richard.Taylor Author

Level 6

17,017 points

Jul 24, 2015 2:11 PM in response to Richard.Taylor

Wow-- That works! Thanks!

Reply

Answer 3

Kurt Lang

Level 9

68,478 points

Jul 24, 2015 2:19 PM in response to Richard.Taylor

You're welcome. 🙂

Reply