program TestAllocate

!=== Example of Allocating a 1G DP Array, filling it, and
!    writing it unformatated.
!   hdk - January 2007.

      integer :: AllocStatus, na, i, GB
      real(kind(1.D0)), allocatable, dimension(:) :: a

        GB=1024**3 ! 1073741824 bytes.
!---DP array, a, is assumed to have 8-byte elements.
        na=GB/8     ! na is the number of DP array  elements.
        print *, "Attempting to allocate ",na," DP elements."
        print *, " "
! Attempt to allocate exactly 1GB of array,
        allocate( a(na), stat=AllocStatus)
        if (AllocStatus  /= 0) then
            print *, "Could not allocate ",na," DP elements."
            stop
          else
            print *, "Did allocate ",na," DP elements."
            print *, " "
        endif

!  Intel compiler uses recordtype='stream'.
!  Other compilers use access='transparent'.

!     open(unit=60, file='/tmp/bigrec.out',status='unknown',  &

      open(unit=60,file='bigrec.out',status='replace',  &

            form='unformatted', action='write',  &
!           recordtype='stream')
            access='transparent')
      print *, "About to fill array, a"
      print *, " "
      do i=1,na
        a(i)=i
      end do
      print *, "Did fill array, a"
      print *, " "
! Write array, x as one logical record.
      print *,"About to write the array, a"
      print *," "
      write(60) na, a
      print *, "Successful write of array, a"
      print *, " "
      deallocate (a)

 end program