move-if-change

   1 #!/bin/sh
   2
   3 # Copyright (C) 1996 Free Software Foundation, Inc.
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 2 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program; if not, write to the Free Software
  17 # Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18
  19 if
  20 test -r $2
  21 then
  22 if
  23 cmp $1 $2 > /dev/null
  24 then
  25 echo $2 is unchanged
  26 rm -f $1
  27 else
  28 mv -f $1 $2
  29 fi
  30 else
  31 mv -f $1 $2
  32 fi