I've created a sparse file with dd. How do I copy contents of another file there, leaving all the zero blocks unallocated?
If I have a sparse file representing a block device, then how can I efficiently restore the file over a network? Ideally, I'd use rsync -S host:file /dev/sdb, but rsync won't write to block devices. ...
I have a sparse file, in which only some blocks are allocated: ~% du -h --apparent-size example 100K example ~% du -h example 52K example I would like to know which blocks of the file are ...