anchor.diff:  
       READ (PDBFIL,'(A4)', IOSTAT=IERR) ATOM(1:4)
       IF (IERR .LT. 0) THEN
  -        WRITE(STDERR, "(A)") "End of file reached with no ATOM recods read."
  +        WRITE(STDERR, "(A)") "End of file reached with no ATOM records read."
           STOP
       END IF
   
  
positive.code: ! Further revised by K.F. SMITH 17/7/91
  ! SGI version 1.00 A. S. Nealis 11/02/1992
  ! - Gives same volume for CA only and complete files
  ! SGI version 1.10 M. O. Mayans 22/02/1994 
  ! - Added carbohydrate support
  ! SGI version 1.15 M. K. Boehm ??/01/1995
  ! - Added SIA as a carbohydrate
  
negative.code:     READ(5,*) XMI, YMI, ZMI
  ENDIF
  
  RADIS = BOX/2.0
  
  ! Two passes are made through the protein file.
  ! 1. Gets statistics including volume and number of residues
  