anchor.diff:  c
   c...  open output file
   c
  -      if(idout.gt.0) open(kw,file=ofile,status="old",access="append")
  +      ierr=izero
  +      if(idout.gt.izero) open(kw,file=ofile,err=40,status="old",
  +     & access="append")
   c
   c...  open input file
   c
  -      ierr=0
  -      if(nwinkx.eq.0) return
  +      if(nwinkx.eq.izero) return
         open(kr,file=wxfile,status="old",err=20)
   c
   c.......read winkler force data and output results, if desired
   c
         call pskip(kr)
  -      nwxtot=0
  -      nlines=0
  +      nwxtot=izero
  +      nlines=izero
         npage=50
         do i=1,nwinkxe
           read(kr,*,err=30,end=30) n,(iwxtmp(j),j=1,ndof),
        &   (wxtmp(j),j=1,ndof)
  -        nnz=0
  +        nnz=izero
           do j=1,ndof
             wxtmp(j)=wxscal(j)*wxtmp(j)
  -          if(iwxtmp(j).ne.0) then
  +          if(iwxtmp(j).ne.izero) then
               nnz=nnz+1
               nwxtot=nwxtot+1
               iwinkx(1,nwxtot)=iwxtmp(j)
  
positive.code: c
   30   continue
          ierr=3
          close(kr)
          return
  c
   2005 format(/)
  
negative.code: c
   20   continue
          ierr=1
          errstrng="read_winkx"
          close(kr)
          return
  c
  