In terminal, type in
cp -Rp /Volumes/<source-volume>/<source-user>/<source-folder>/ /Volumes/<destination-volume>/<destination-folder>/
Destination folder should be a new folder you are creating.
If you get info on the new folder after running this you can see the folder size increase.
cp -Rp /Volumes/Macintosh HD/User/Bob/Desktop/stufftocopy/ /Volumes/external/newfolder
It will copy and display errors for anything it can’t copy but without stopping.
*If your directory names contain spaces put quotes around the path
cp -Rp "/Volumes/Macintosh HD/User/Bob/Desktop/stufftocopy/" /Volumes/external/newfolder
You can use
cp as suggested or
rsync, but in the case of I/O Error sometimes it won’t work.
So in this case, you can use
dd tool for specific files which were corrupted.
ddstands for “disk duplication”. This is a command-line utility
bundled with Mac OS X. A free version for Windows is also available.
Be extremely careful, even if you are familiar with command line,
because dd can cause unrecoverable damage to your data if you don’t
specify correctly input and output. You have been warned.
The arguments of dd are straight-forward:
- if=path_of_file_with_IO_errors specifies input path
- of=path_of_clean_copy_to_create specifies output path
- conv=noerror,sync tells dd to be fault-tolerant
Your output path should not be on the same disk as the damaged file.
Actually, you shouldn’t continue using the card or disk with I/O
errors, because it’s likely to cause more problems in the future.
After recovery the data, you should scrap it or at most use it to
store unimportant stuff.
Due to I/O errors, dd can take more time to create the clean copy than
a normal copy would take.
But it’s really worth the wait, because now we have a clean file on
which we can use our arsenal of diagnostics, preview and video
I/O errors are a serious business, and scrapping the card after
recovering the videos is probably the RIGHT THING TO DO. You should
also consider that some amount of footage won’t be recovered, or with
a less-than-stellar quality.
dd if=/Volumes/CD/broken_movie.avi of=~/Movies/broken_movie.avi conv=noerror,sync
I use Beyond Compare for exactly this purpose (it’s commercial software but has a free trial). You tell it to copy a file, a folder, or a whole drive or any combination and it finishes to the end of the task and reports problems as it goes. This doesn’t help recover any corrupted files, but it will finish the job no matter how many problems it encounters.
Teracopy has released a Mac version which you can download from the Apple store.