anchor.diff:  c
   c...  open input file and read entries
   c
  -      ierr=0
  -      numflt=0
  -      if(numfn.ne.0) then
  +      ierr=izero
  +      numflt=izero
  +      if(numfn.ne.izero) then
           call fill(fault,zero,ndof*numfn)
           call ifill(nfault,izero,3*numfn)
           open(kr,file=spfile,status="old",err=20)
  
positive.code: c
   20   continue
          ierr=1
          close(kr)
          return
  c
  
negative.code: c
  c     Error codes:
  c         0:  No error
  c         1:  Error opening input file (only if numfn.ne.zero)
  c         2:  Error opening output file
  c         3:  Read error
  c         4:  Write error
  c
  
        include "implicit.inc"
  c
  c...  parameter definitions
  c
        include "ndimens.inc"
        include "nconsts.inc"
        include "rconsts.inc"
  c
  c...  subroutine arguments
  c
        integer numfn,numflt,numnp,kr,kw,kp,idout,idsk,ierr
        integer nfault(3,numfn)
        double precision fault(ndof,numfn)
        character spfile*(*),ofile*(*),pfile*(*),errstrng*(*)
  c
  c...  intrinsic functions
  c
  