Can a file that was originally sparse and expanded be made re-sparse

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http://unix.stackexchange.com – I know that copying or transferring what was originally a sparse file without using a utility that understands sparse files will cause the 'holes' to be filled out. Is there a method or utility to turn what was once a sparse file back to sparse? For Example: create sparse file: % dd if=/dev/zero of=TEST bs=1 count=0 seek=1G # do some op that pads out the holes % scp TEST localhost:~/TEST2 % ls -lhs TEST* 0 -rw-rw-r--. 1 tony tony 1.0G Oct 16 13:35 TEST 1.1G -rw-rw-r--. 1 tony tony 1.0G Oct 16 13:37 TEST2 Is there some way to: % resparse TEST2 to get: 0 -rw-rw-r--. 1 tony tony 1.0G (HowTos)