Re: posix_fallocate

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Sun, 17 Nov 2013 23:49:50 +0100
    From:        Rhialto <rhialto%falu.nl@localhost>
    Message-ID:  <20131117224950.GH23546%falu.nl@localhost>

  | Wasn't there some (proposed? actual?) interface to find holes in files?

I was told off-list about SEEK_HOLE and SEEK_DATA that allow (if the
filesys supports them) apps to jump to the next hole, then end of hole,
and that way work out where the holes are.

According to the linux man page, they exist there, and FreeBSD DragonFly and
Solaris - and might come to posix.

Personally, I think the underlying structure of files should not be made
visible to apps at all - they should just see a byte stream (perhaps with
an advisory useful block size to write in).

kre