btrfs-map-logical(8)
====================

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

SYNOPSIS
--------
*btrfs-map-logical* <options> <device>

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

SEE ALSO
--------
`mkfs.btrfs`(8)