Re: dd - proper use or more suitable program

[Pascal Hambourg]

Le 12/11/2016 à 18:22, Richard Owlett a écrit :

ddrescue /dev/sda /mnt/defective_drive.img /mnt/defective_drive.log
(...)
Can this be run as a user, or are root permissions required.

Unless the user has read permission on the raw device, it must be run as 
root.

My defective drive is /dev/sdc .
Partition /dev/sdb6 {formatted ext4} is much larger than the defective
drive.
/dev/sdb is a 1 TB rotating platter drive connected via USB.
How do I mount it and run ddrescue?

Mount what ?
You don't mount anything from the defective drive.
You mount the filesystem which will receive the disk image file anywhere 
you like with mount. In the above example it was expected to be mounted 
on /mnt, the usual temporary mount point. So :

mount /dev/sdb6 /mnt

The file manager of your desktop environment may have already mounted it 
for you elsewhere in /media/. Check df or mount.