Re: [Libguestfs] [PATCH 1/2] New API: btrfs_filesystem_show

Richard W.M. Jones
Thu, 05 Mar 2015 12:59:12 -0000

AFAICT this API doesn't work:

  $ ./run guestfish -N fs:btrfs btrfs-filesystem-show /dev/sda1
  libguestfs: error: btrfs_filesystem_show: /dev/sda1:

When I tried the btrfs-filesystem-show-all API, I see a lot of
structure in the output:

  $ ./run guestfish -N fs:btrfs btrfs-filesystem-show-all
  Label: none  uuid: f7754d86-baa1-40e7-a563-46976e81d64c
         Total devices 1 FS bytes used 28.00KiB
         devid    1 size 99.88MiB used 12.00MiB path /dev/sda1

  Btrfs v3.18

Usually we should try to turn that text into structs, otherwise every
consumer of libguestfs has to write parsing code themselves.

*However* in this case I'm having a hard time understanding why anyone
would want to use the API.  Most likely if they were debugging a btrfs
problem, they'd be using 'virt-rescue' and would be able to run
arbitrary commands.  Some of the other information, like UUID and
label is available through other APIs (eg. get-uuid).  Other
information like the layout of devices could be modelled with some
very complex structs on the libguestfs side, but does anyone need
this?

Rich.

--
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