Copy sparse files

cp --sparse=always <SRC> <DST>
This causes cp to detect and omit large blocks of nulls. Sparse files are useful for implying a lot of disk space without actually having to write it all out. http://en.wikipedia.org/wiki/Sparse_file You can use it in a pipe too: dd if=/dev/zero bs=1M count=5 |cp --sparse=always /dev/stdin SPARSE_FILE
Sample Output
# create a file with zeroes
$ dd if=/dev/zero bs=1M count=5 of=full-5m 
# copy with sparsity detection
$ cp --sparse=always full-5m sparse-5m

# they look the same...
$ ls -lah full-5m sparse-5m
-rw-r--r-- 1 h3xx users 5.0M Sep  7 03:05 full-5m
-rw-r--r-- 1 h3xx users 5.0M Sep  7 03:04 sparse-5m

# but they're different!
$ du -h full-5m sparse-5m
5.1M    full-5m
5.0K    sparse-5m

4
By: h3xx
2011-09-07 08:02:50

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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