#!/bin/csh -f

umask 66

set tempfile = /tmp/changekey.$USER.$$

echo "Enter old key:"
set oldkey = $<
while (1)
  echo "Enter new key:"
  set newkey = $<
  echo "Retype new key:"
  set renew = $<
  if ("$newkey" == "$renew") break
end

foreach i ($*)
  crypt $oldkey <$i
  while (1)
    echo "Ok to recrypt $i? (y or n)"
    set answer = $<
    switch ($answer)
    case y:
      crypt $oldkey <$i | crypt $newkey > $tempfile
      mv $tempfile $i
    case n:
      break
    endsw
  end
end