This option, when added via
  TESTS_ENVIRONMENT = [...] $(top_builddir)/run --test
allows us to run the tests and only print the full output (including
debugging etc) when the test fails.

Another instance of 'truncate' command.

See commit 39df80dcc0e485e69048bddbf33c259ce532e50d for an
explanation.

RHEL 5-era autoconf did not define these, so define them manually
when they are missing.

Define builddir as '.'  The scripts require this.  It won't work
in the srcdir != builddir case, but we don't care about that for
RHEL 5.

This commit also moves the builddir / abs_srcdir variable setting
above the include of subdir-rules.mk, in case that include uses
these variables.

Useful script:

  for f in $(find -name Makefile.am | xargs fgrep '$(abs_srcdir)' -l) ; do
    if ! grep -q '^abs_srcdir' $f; then
      echo missing in $f
    fi
  done

This API makes device names canonical, eg. /dev/vda1 -> /dev/sda1.

I used scsi_debug to create a 4k sector virtual disk:

  modprobe scsi_debug dev_size_mb=128 sector_size=4096

I then used 'gdisk' to create lots of partitions, and used 'hexdump'
to examine what was written to disk.

Note that this support is optional: To enable it, install the
ocaml-gettext library from
http://forge.ocamlcore.org/projects/ocaml-gettext .  If this library
is not installed, then configure detects this and inserts dummy
gettext functions that do nothing.