The main issue was btrfs subvolumes (also a feature of ZFS). libguestfs previously made the assumption that /dev device ≡ mountable volume. So for example, if you asked libguestfs to inspect a guest and tell you the root filesystem, it would return the name of the device.
The changes made to libguestfs (which are backwards compatible) add the concept of a “mountable” point which could be a device for regular filesystems or a subvolume for btrfs (or something else; the system is now extensible).
This work was done by Matt Booth to support virt-v2v.
podwrapper.pl: wrote guestfs-release-notes.1
Wide character in print at /home/ebal/dnl/PKGBUILDs/kvm/libguestfs/src/libguestfs-1.22.1/podwrapper.pl line 506.
podwrapper.pl: wrote ./html/guestfs-release-notes.1.html
This shouldn’t happen at /usr/share/perl5/core_perl/Text/Wrap.pm line 84.
I am Richard W.M. Jones, a computer programmer. I have strong opinions on how we write software, about Reason and the scientific method. Consequently I am an atheist [To nutcases: Please stop emailing me about this, I'm not interested in your views on it] By day I work for Red Hat on all things to do with virtualization. I am a "citizen of the world".
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Richard WM Jones 
What kind of new features added to btrfs will require changes to libguestfs?
The main issue was btrfs subvolumes (also a feature of ZFS). libguestfs previously made the assumption that
/dev device ≡ mountable volume. So for example, if you asked libguestfs to inspect a guest and tell you the root filesystem, it would return the name of the device.The changes made to libguestfs (which are backwards compatible) add the concept of a “mountable” point which could be a device for regular filesystems or a subvolume for btrfs (or something else; the system is now extensible).
This work was done by Matt Booth to support virt-v2v.
It was sub volumes I was thinking about in particular. So that’s very impressive.
any hint ?
podwrapper.pl: wrote guestfs-release-notes.1
Wide character in print at /home/ebal/dnl/PKGBUILDs/kvm/libguestfs/src/libguestfs-1.22.1/podwrapper.pl line 506.
podwrapper.pl: wrote ./html/guestfs-release-notes.1.html
This shouldn’t happen at /usr/share/perl5/core_perl/Text/Wrap.pm line 84.
make error
Is this a hard error? What is your locale? Is it UTF-8? (Run the
localecommand).I actually thought I had fixed all of these “wide character in print” bugs in this commit.
hard error:
make: *** [all] Error 2
LANG=en_US.utf8
LC_ALL=en_US.utf8
This isn’t a good place for support. Please send the complete build log to the mailing list.
sorry about posting this here – thought it was something extremely trivial