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xfs_bmap(8)                 System Manager's Manual                xfs_bmap(8)

NAME
       xfs_bmap - print block mapping for an XFS file
SYNOPSIS
       xfs_bmap [ -adlpv ] [ -n num_extents ] file
       xfs_bmap -V
DESCRIPTION
       xfs_bmap prints the map of disk blocks used by files in an XFS filesys-
       tem.  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.
OPTIONS
       -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.  How-
              ever if the -d option is used, no DMAPI read event will be  gen-
              erated 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 (preallo-
              cated)  extents  that  do  not contain written data. With the -v
              option, the flags column will show which  extents  are  preallo-
              cated/unwritten.
       -v     Shows  verbose  information.  When this flag is specified, addi-
              tional 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.
       -V     Prints the version number and exits.
SEE ALSO
       xfs_fsr(8), xfs(5).

                                                                   xfs_bmap(8)