AppleDouble

From Just Solve the File Format Problem
(Difference between revisions)
Jump to: navigation, search
Line 21: Line 21:
 
* [http://tools.ietf.org/html/draft-newman-macbin-binhex-harmful-00 MacBinary and Binhex 4.0 considered harmful]
 
* [http://tools.ietf.org/html/draft-newman-macbin-binhex-harmful-00 MacBinary and Binhex 4.0 considered harmful]
 
* [http://web.archive.org/web/20120602061209/http://support.apple.com/kb/TA20578 Apple KnowledgeBase notes about AppleDouble]
 
* [http://web.archive.org/web/20120602061209/http://support.apple.com/kb/TA20578 Apple KnowledgeBase notes about AppleDouble]
 +
 +
[[Category:Macintosh]]

Revision as of 12:46, 24 October 2013

File Format
Name AppleDouble
Ontology
MIME Type(s) multipart/appledouble
AppleDouble is one of the systems used to store the Resource Fork of Macintosh files on filesystems not natively supporting it, something which became necessary when Apple moved to Unix-based operating systems instead of "classic" MacOS. AppleSingle is an alternative format to accomplish the same end, combining all the forks plus a metadata header in one file instead of keeping separate files like AppleDouble. While both AppleSingle and AppleDouble were introduced for use with early Unix-based Apple systems, AppleDouble survived as the main method of storing files with resource forks on OS X systems if a filesystem is used that doesn't directly support such forks.

The AppleDouble format keeps the data fork of the file in its original format and filename (this is the main file, as used by non-Mac operating systems, and for many file formats, the only one that matters), and creates a second file with the resource fork as well as Finder metadata. The second file has the filename of the main file with "._" (a dot and an underscore) preceding it. If it was encoded for transmission, Base64 was generally used.

Format detail links

Utilities

Other links

Personal tools
Namespaces

Variants
Actions
Navigation
Toolbox