      SUBROUTINE GET_INF(IUNIT)
*
***** ***************************************************************
*
*---- Gecontroleerd opvragen invoerfile
*
*---- Flip Witte, LUW, 130594
*
***** ***************************************************************
*
      CHARACTER CFIL*35
      LOGICAL AANW
*
      GOTO 20
10    WRITE(6,900)'Fout; invoerfile is: '
20    READ(5,900,ERR=10)CFIL
      INQUIRE(FILE=CFIL,EXIST=AANW)
      IF (.NOT.AANW) GOTO 10
      OPEN(IUNIT,FILE=CFIL,STATUS='OLD')
*
900   FORMAT(A35,$)
*
      RETURN
      END