BTRFS-MAP-LOGICAL(8)            Btrfs Manual            BTRFS-MAP-LOGICAL(8)

NAME         top

       btrfs-map-logical - map btrfs logical extent to physical extent

SYNOPSIS         top

       btrfs-map-logical <options> <device>

DESCRIPTION         top

       btrfs-map-logical can be used to find out what the physical offsets
       are on the mirrors, the result is dumped into stdout in default.

       Mainly used for debug purpose.

OPTIONS         top

       -l|--logical <logical_num>
           Logical extent to map.

       -c|--copy <copy>
           Copy of the extent to read(usually 1 or 2).

       -o|--output <filename>
           Output file to hold the extent.

       -b|--bytes <bytes>
           Number of bytes to read.

EXIT STATUS         top

       btrfs-map-logical will return 0 if no error happened. If any problems
       happened, 1 will be returned.

SEE ALSO         top


COLOPHON         top

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Btrfs v4.6.1                     07/16/2016             BTRFS-MAP-LOGICAL(8)