holes in files

[Dan Bernstein]

In article <18823 at rpp386.cactus.org> jfh at rpp386.cactus.org (John F Haugh II) writes:
> The example of checksumming the results of stat() works pretty well.
> A few weeks back there was some discussion about date roll back and
> so on.  Keeping track of the exact contents of the entire inode and
> file might be one form of copy protection or file validation.  You
> could ignore the parts that change (like st_atime), but keep track
> of the rest (like st_mtime, st_blocks, etc) along with file data.

Right. Another realistic example is that many sites run a program to
search for all files of a particular type---setuid, for instance. Some
such programs work by generating an ls-type output, then ``diff''ing
the list from the previous list and sending a message to the admin about
any changes. If the block size changes sporadically, the admin will get
false alarms.

---Dan