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What are the weird files that start with ._ that pc users get when I send zips?

When I send files that I zip using Stuiffit to pc users they get the files plus an equal number of files that start with ._ Does anybody know what these are and how to get rid of them?


Thanks!


Karen

iMac, Mac OS X (10.6.8), Using Stuffit Destinations

Posted on Apr 6, 2013 12:46 AM

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Posted on Apr 6, 2013 7:45 AM

Dot files are invisible files that OS X uses to display positions of files and folders icon for instance when you open a folder.

That is indeed what a .DS_Store file does, but that's not the ones Bogies is referring to.


There are various other items that start with a period, such as .Trashes. Every drive gets a trash folder, just as Windows does to each of its drives. While it hides its own trash folders from view, Windows doesn't recognize OS X's version of the trash folder, so you see it.


But you're likely talking about these. Every file you copy from OS X to a DOS/Windows formatted drive gets a ._ file. The Mac OS has a twin file system; the data fork, and the resource fork. Windows has only a data fork.


In order for OS X to maintain the resource fork data on a Windows drive, it has to write the resource data as a separate data fork file. So a file named foo.tif will also get a ._foo.tif file on the drive. Mac users don't see them since UNIX automatically hides anything that starts with a period. When you copy the file back to OS X, the data and resource fork info is combined again into a normal Mac file.


Most of the time, removing these are no big deal. They hold simple data like Type and Creator codes, modification dates, icons, etc. Others, like Mac Type 1 PostScript or Mac legacy TrueType fonts have all of the font data in the resource fork. Delete the ._ files for those types of fonts, and you're left with nothing.

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Question marked as Top-ranking reply

Apr 6, 2013 7:45 AM in response to Bogies

Dot files are invisible files that OS X uses to display positions of files and folders icon for instance when you open a folder.

That is indeed what a .DS_Store file does, but that's not the ones Bogies is referring to.


There are various other items that start with a period, such as .Trashes. Every drive gets a trash folder, just as Windows does to each of its drives. While it hides its own trash folders from view, Windows doesn't recognize OS X's version of the trash folder, so you see it.


But you're likely talking about these. Every file you copy from OS X to a DOS/Windows formatted drive gets a ._ file. The Mac OS has a twin file system; the data fork, and the resource fork. Windows has only a data fork.


In order for OS X to maintain the resource fork data on a Windows drive, it has to write the resource data as a separate data fork file. So a file named foo.tif will also get a ._foo.tif file on the drive. Mac users don't see them since UNIX automatically hides anything that starts with a period. When you copy the file back to OS X, the data and resource fork info is combined again into a normal Mac file.


Most of the time, removing these are no big deal. They hold simple data like Type and Creator codes, modification dates, icons, etc. Others, like Mac Type 1 PostScript or Mac legacy TrueType fonts have all of the font data in the resource fork. Delete the ._ files for those types of fonts, and you're left with nothing.

Apr 6, 2013 7:12 AM in response to Bogies

Dot files are invisible files that OS X uses to display positions of files and folders icon for instance when you open a folder.


One of the most famous of these is .ds_store files.


If you manage to delete them, OS X will just remake them again, the only way to remove them is to send the files to Windows in a virtual machine program and remove them there, then zip them up and send them off from Windows instead.


Windows in BootCamp or Virtual Machine?

Apr 6, 2013 4:53 PM in response to Bogies

Bogies wrote:


Thank you both! But, is there any way to remove the ._ files before I zip them to send?


Transfer the files to Windows, then you will see the invisible OS X files and can delete them because Windows doesn't use them anyway.


Then zip the files and either return them to OS X to send off or send them off directly from Windows.



There is a program that will remove the hidden files before sending over a shared network with Windows, but removing those files on OS X causes severe issues.

Apr 6, 2013 5:11 PM in response to Bogies

Appledouble


Do they exist before zipping ? (you'll need to use Terminal 'ls -Al' or some utility to show invisible files in Finder)

If not, then presumably stuffit or the receiving pc is creating them... older versions of stuffit had a 'preserve macintosh content' option which could be de-selected to avoid this.


If they already exist, there's a terminal command DOT_CLEAN which removes them, also a paid-for preference pane whose name escapes me.

Apr 6, 2013 7:27 PM in response to andyBall_uk

checking further - it is stuffit that causes this, testing here at least.

You can likely prevent it really quite easily by selecting the files you wish to zip first in Finder, then using Command-Option-I & deselecting the 'hide extension' box ) so that it is empty).


There is a hidden preference setting for Destinations (at least, hidden to me, unlike earlier versions) which when modfied, prevents these ._ files from being created in the zip. It's named preEncodingFormat, and is set to 'double' (as in AppleDouble?) by default. Remove that & no more ._

Apr 7, 2013 5:58 AM in response to Bogies

for a single file, the info window - hide extension box will be empty or checked... you want empty.

for multiple files, using Command-Option-I (the 'inspector' - the box can also be part-checked - a dash, so you'd have to click it empty. In checking here, it was always that which led to stuffit creating the extra files, but I only looked at a few.


the preference is hidden from the regular window view, so far as I could see.

It's a line in a file named com.stuffit.StuffIt-Destinations.plist in Home/Library/Preferences/ and needs altering with a plist editor. Easier to remove the hide extension attribute, assuming that works for you too. If not, get http://www.nightproductions.net/prefsetter.html & I'll walk you through it.


I'd ask the makers of stuffit too - I may be missing the easy way to alter it, but couldn't find mention on their website. Or use Apple's bulit-in zipper, which doesn't have that issue, that I saw.

Apr 7, 2013 6:24 AM in response to Bogies

Yes, there is.


You must use the zip command in a Terminal window.


Open Terminal and type


zip -j ~/Desktop/archive.zip


select the file/files you want to add to archive.zip, drag it/them into the Terminal window and press return.


You'll get a zipped file without the annoying and useless (for Microsoft Windows) files beginning with ._


PS


-j prevent zip to store the file path

archive.zip can be any name you like

Apr 8, 2013 12:38 AM in response to Bogies

Thank you all - you've been very helpful and I really appreciate it! I'm not much of a techie and found a good, easy solution - I downloaded WinZip Mac and it works perfectly! I should have realized it was Stuffit Destinations because I didn't have this problem with my old stuffit.


Thanks again - problem solved!


Karen : )

What are the weird files that start with ._ that pc users get when I send zips?

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