build: Use $host_os variable to clarify configure.ac * configure.ac: Use $host_os instead of $canonical_host_type when operating system is being tested. * m4/acinclude.m4(OCTAVE_HOST_TYPE): Rename macro to OCTAVE_CANONICAL_HOST to be similar to Autoconf macro of same purpose. Guarantee that $host, $host_cpu, $host_vendor, and $host_os all have a value.

#!/bin/sh
#
# Like mv $1 $2, but if the files are the same, just delete $1.
# Status is 0 if $2 is changed, 1 otherwise.

if test -r $2; then
  if cmp $1 $2 > /dev/null; then
    echo $2 is unchanged
    rm -f $1
  else
    mv -f $1 $2
  fi
else
  mv -f $1 $2
fi