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       xfs_bmap - print block mapping for an XFS file


       xfs_bmap [ -adlpv ] [ -n num_extents ] file


       xfs_bmap  prints  the  map  of  disk  blocks  used  by  files in an XFS
       filesystem.  The map lists each extent used by the  file,  as  well  as
       regions  in the file that do not have any corresponding blocks (holes).
       Each line of the listings takes the following form:

              extent: [startoffset..endoffset]: startblock..endblock

       Holes are marked by replacing the startblock..endblock with hole.   All
       the  file  offsets  and disk blocks are in units of 512-byte blocks, no
       matter what the filesystem’s block size is.


       -a     If this  option  is  specified,  information  about  the  file’s
              attribute fork is printed instead of the default data fork.

       -d     If  portions  of  the file have been migrated offline by a DMAPI
              application, a DMAPI read event will be generated to bring those
              portions  back  online  before  the  disk  block map is printed.
              However if the -d option is used, no DMAPI read  event  will  be
              generated for a DMAPI file and offline portions will be reported
              as holes.

       -l     If this option is used, then

                   <nblocks>  blocks

              will be appended to each line.  nblocks is  the  length  of  the
              extent described on the line in units of 512-byte blocks.

              This flag has no effect if the -v option is used.

       -n num_extents
              If this option is given, xfs_bmap obtains the extent list of the
              file in groups of num_extents extents. In  the  absence  of  -n,
              xfs_bmap  queries  the  system  for the number of extents in the
              file and uses that value to compute the group size.

       -p     If  this  option  is  used,  xfs_bmap  obtains   all   unwritten
              (preallocated)  extents  that  do not contain written data. With
              the -v option, the flags column  will  show  which  extents  are

       -v     Shows   verbose   information.  When  this  flag  is  specified,
              additional AG specific information is appended to each  line  in
              the following form:

                   agno (startagoffset..endagoffset) nblocks flags

              A second -v option will print out the flags legend.


       xfs_fsr(8), xfs(5).