PROGRAM CHKEND
! This file: http://ftp.aset.psu.edu/pub/ger/fortran/hdk/endian.f90
!
! by Code Tuning co-guide, 1998 Lahey Fortran Users' Conference
! Check what endian this program is running on.
!     ------------------------------------------------------------------
      INTEGER(4) I, ASCII_0, ASCII_1, ASCII_2, ASCII_3
!     ------------------------------------------------------------------
      PARAMETER(ASCII_0 = 48, ASCII_1 = 49,    &
                ASCII_2 = 50, ASCII_3 = 51)
!     ------------------------------------------------------------------
      COMMON // I
!     ------------------------------------------------------------------
      I = ASCII_0 + ASCII_1*256 + ASCII_2*(256**2) + ASCII_3*(256**3)
      CALL SUB()
!     ------------------------------------------------------------------
      END
      SUBROUTINE SUB()
!     ------------------------------------------------------------------
      CHARACTER(4) I
!     ------------------------------------------------------------------
      COMMON // I
!     ------------------------------------------------------------------
      WRITE(*,*) ' Integer structure: ', I
      WRITE(*,*) ' Byte order:        ', '0123'
      WRITE(*,*)
!     ------------------------------------------------------------------
      IF (I == '0123') THEN
        WRITE(*,*) ' Machine is Little-Endian '
        RETURN
      ENDIF
!     ------------------------------------------------------------------
      IF (I == '3210') THEN
        WRITE(*,*) ' Machine is Big-Endian '
        RETURN
      ENDIF
!     ------------------------------------------------------------------
      WRITE(*,*) ' Mixed endianity machine ... '
!     ------------------------------------------------------------------
      RETURN
      END