In the last episode (Nov 11), Matthias Apitz said: > What is the best method to overwrite the blocks of a given file with bytes > of 0x00, i.e. not to O_TRUNC away the blocks to the freelist of the file > system, but overwrite the old blocks? > > I've checked > > $ dd if=/dev/zero of=file count=4 > > but dd(1) opens the file with O_RDWR|O_CREAT|O_TRUNC which for sure will > give away the old blocks and adquire new blocks. Any idea?
conv=notrunc (note that this will only help with ufs; zfs is always copy-on-write, so newly-written data never overwrites the old blocks) -- Dan Nelson dnel...@allantgroup.com _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"