reading hammer inode contents

Matthew Dillon dillon at
Wed Sep 30 09:38:07 PDT 2009

:How is it possible for me to read the contents on i-nodes in hammer?
:Also list the i-nodes that are in use or used earlier?

    There is no hammer directive that will do this in a human readable way
    (well, except 'hammer show' which has the nasty side effect of wanting
    to dump everything, including bulk data).

    But it is easy to dump the raw inodes, including any historical
    (deleted or replaced older versions) of inodes using the

    You would have to write some C code and you would have to learn a bit
    about constructing B-Tree key ranges for the ioctl, and then you
    would have to parse out the records from the mirroring stream.
    Then you could print out the inode records in a human readable form.

    It would make a nice little mini-project if someone wants to try
    writing the extension to the hammer utility to do it.  There are some
    good examples... the 'hammer mirror-dump' directive parses stuff out
    into a human readable form so you have to glue together constructing
    the correct B-Tree range with some conditionals to just extract the
    inode records and then push the results through code similar to what
    hammer mirror-dump does to print the inodes out in human-readable form.

    What do you need the inode data for?

					Matthew Dillon 
					<dillon at>

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