Maintain File Ownership & Permissions When Copying With Duplicate Exactly in OS X
Mac OS X 10.7 and OS X 10.8 include a nice new ability to be able to duplicate and paste files exactly. Basically this means that if a file is owned by another user, Duplicate Exactly and Paste Exactly will preserve the files original ownership and permissions, rather than copy the file with the current user becoming the new owner.
Select a file or folder within the Finder and hit Command+Option+Shift+D to perform an exact duplication. You will be presented with a window to authenticate the copy to allow the ownership state to maintain consistency.
The duplicate will be placed alongside the original, maintaining ownership integrity.
Similarly, there is also a new feature that lets you Paste Exactly, maintaining the same ownership and permissions when using cut and paste in the OS X Finder. This is activated with Command+Shift+Option+V after a file or folder has already been placed in the clipboard buffer.
These two tips are geared for more advanced users and administrators who are altering another users files or directories. Try them out the next time you are editing another users files and save yourself a potential headache.