Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have mounted a usb thumb drive into my MBP.

Here is the partial output from mount

/dev/disk2s1 on /Volumes/KINGSTON (ntfs, local, nodev, nosuid, read-only, noowners)

When I tried

$ dd if=/dev/disk2s1 of=usb.img bs=512
dd: /dev/disk2s1: Resource busy

It seems like 'Resource busy' error prevent me from using dd on the thumb drive.

Is there any solution?

share|improve this question
up vote 3 down vote accepted

Use Disk Utility to unmount the drive, and possibly also to do the copy; this has the advantage that you can mount the image afterward if you need to get at any files in it. If you prefer the command line, hdiutil is the command line version of Disk Utility.

share|improve this answer

Unmount the volume after you learn its device, then repeat.

share|improve this answer

Maybe unmount usb drive first and then rerun dd?

share|improve this answer

On Mac OS X (Yosemite) use:
sudo diskutil unmount /dev/[your device]

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .