[Libguestfs] ANNOUNCE: "attach-method" is now "backend"

Starting with libguestfs 1.22, "attach methods" will be known as "backends" (one word, no space or hyphen). There are new APIs 'guestfs_set_backend', 'guestfs_get_backend', and a new environment variable 'LIBGUESTFS_BACKEND'. Furthermore, the default backend, running qemu directly, is now called "direct" instead of "appliance". (Note that distros can change the default by compiling with ./configure --with-default-backend=..., and Fedora does change this to "libvirt"). FWIW there are three backends (same as before): - direct (a.k.a. appliance): Run qemu directly - libvirt: Manage the appliance with libvirt - unix: Connect to a Unix socket (for libguestfs live) For backwards compatibility, the old APIs continue to be supported, along with the LIBGUESTFS_ATTACH_METHOD environment variable, and the synonym "appliance" instead of "direct". Because these are part of the C API they will be supported forever, but you can get a warning about using them by compiling with -DGUESTFS_WARN_DEPRECATED=1. See this large but mostly mechanical patch: https://github.com/libguestfs/libguestfs/commit/68990840b64491b39ab8da5f1... Also note this change will be included in RHEL 7. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top