writing and reading derived types with pointers

Hi All,

I'm trying to save a write a derived type that contains a pointer to an unformatted file for later reading.  Below is a test version.  The derived type sol in module dType is separate because I'm patching together various Fortran codes (F95 and F77, etc).  The current version of the code "saves" sol1, but it seems to only save the pointer references, not their values, so when sol1 is deallocated, sol2 also becomes unreferenced.  I'm sure my hack on the UDTIO is not correct.

Any help would be appreciated (I'm still trying to figure out UDTIO).  Thanks

-joe

   module dType
      implicit none
      type, public :: sol
         integer:: n
         real(8), pointer:: vec(:)
      end type sol
   end module dType

   module dType_io
      use dType
      implicit none
   contains

   subroutine write_sol(dtv, unit, iostat, iomsg)
      class(sol), intent(in) :: dtv
      integer, intent(in)             :: unit
      integer, intent(out)            :: iostat
      character(*), intent(inout)     :: iomsg

      write(unit, iostat=iostat, iomsg=iomsg) dtv%n
      write(unit, iostat=iostat, iomsg=iomsg) size(dtv%vec)
      write(unit, iostat=iostat, iomsg=iomsg) dtv%vec
   end subroutine write_sol

   subroutine read_sol(dtv, unit, iostat, iomsg)
      class(sol), intent(inout)  :: dtv
      integer, intent(in)                 :: unit
      integer, intent(out)                :: iostat
      character(*), intent(inout)         :: iomsg

      integer allocSize

      ! read is sol type, but allocate pointer space as needed.
      read(unit, iostat=iostat, iomsg=iomsg) dtv%n
      read(unit, iostat=iostat, iomsg=iomsg) allocSize
      allocate( dtv%vec(allocSize) )
      read(unit, iostat=iostat, iomsg=iomsg) dtv%vec
   end subroutine read_sol
   end module dType_io

   program directAccess
      use dType
      implicit none
      integer, parameter :: dp = kind(0d0)
      type(sol):: sol1, sol2
      integer solUnit, n, sze
      integer i

      sol1%n = 10
      allocate( sol1%vec(sol1%n) )
      sol1%vec = [ (real(i),i=1,sol1%n) ]

      open(newunit=solUnit, file='test.sol', form='unformatted', status='replace', action='write')
      write(solUnit) sol1
      close(solUnit)

      open(newunit=solUnit, file='test.sol', form='unformatted', status='old', action='read')
      read(solUnit) sol2

      deallocate( sol1%vec ); nullify(sol1%vec) ! this will cause sol2 to lose reference

      close(solUnit)
      stop
   end program directAccess