anchor.diff:  c
   c...  open input file
   c
  -      ierr=0
  -      numrot=0
  -      nget=1
  +      ierr=izero
  +      numrot=izero
  +      nget=ione
         open(kr,file=skfile,status="old",err=10)
   c
  -c...  get units, returning error 2 if they aren't found.
  +c...  get units, returning error 5 if they aren't found.
   c
  -      call get_units(kr,ierr,nget,units_defined,units,def)
  -      if(ierr.eq.2) return
  +      call get_units(kr,nget,units_defined,units,def,ierr,errstrng)
  +      if(ierr.ne.izero) return
         rotation_units=units(1)
   c
   c... scan the file, counting the number of entries.
  
positive.code: c~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  c
  c
        subroutine scan_skew(nskdim,numrot,kr,ierr,rotation_units,skfile)
  c
  c...  subroutine to perform an initial scan of the skew rotation file
  c     to determine the number of predefined skew rotations and the
  
negative.code: c         0:  No error
  c         1:  Error opening input file (this should not produce an
  c             exception since skew BC are optional)
  c         3:  Read error
  c         5:  Units not specified
  c
        include "implicit.inc"
  c
  c...  parameter definitions
  c
        include "ndimens.inc"
        include "nconsts.inc"
  c
  c...  subroutine arguments
  c
        integer numrot,kr,ierr
        character rotation_units*(*),skfile*(*),errstrng*(*)
  c
  c...  local constants
  c
        character def(1)*14
        data def/"rotation_units"/
  