anchor.diff:    character(len=:), allocatable              :: s_buffer     !< Buffer string.
     character(len=:), allocatable              :: aux
     integer(I4P)                               :: np, pos, of
  -  integer(I4P)                               :: nx1,nx2,ny1,ny2,nz1,nz2
     !---------------------------------------------------------------------------------------------------------------------------------
   
     !---------------------------------------------------------------------------------------------------------------------------------
  
positive.code:   !< Function for reading field of scalar variable (I4P, 1D array).
    !---------------------------------------------------------------------------------------------------------------------------------
    implicit none
    character(*),              intent(IN)  :: var_location ! location of variables: CELL for cell-centered, NODE for node-centered
    character(*),              intent(IN)  :: varname      ! variable name
    integer(I4P),              intent(OUT) :: NC_NN        ! number of cells or nodes
    integer(I4P),              intent(OUT) :: NCOMP        ! number of components
    integer(I8P), allocatable, intent(OUT) :: var(:)       ! variable to be saved
    integer(I4P), optional,    intent(IN)  :: npiece       ! Number of the piece to read (by default: 1)
    integer(I4P), optional,    intent(IN)  :: cf           !< Current file index (for concurrent files IO).
    integer(I4P)                           :: E_IO         ! Input/Output inquiring flag: $0$ if IO is done, $> 0$ if IO is not done
    integer(I4P)                           :: rf           !< Real file index.
    character(len=:), allocatable          :: s_buffer     !< Buffer string.
    character(len=:), allocatable          :: fmt
  
negative.code:   !<    - output is 3D-rank (packed API): var[1:N_COL,nx1:nx2,ny1:ny2,nz1:nz2].
    !<
    !< @note Note that the output that must be passed change depending on the data variables type.
    module procedure VTK_VAR_XML_SCAL_1DA_R8_READ,VTK_VAR_XML_SCAL_3DA_R8_READ, & ! real(R8P)    scalar    1D/3D array
                     VTK_VAR_XML_SCAL_1DA_R4_READ,VTK_VAR_XML_SCAL_3DA_R4_READ, & ! real(R4P)    scalar    1D/3D array
                     VTK_VAR_XML_SCAL_1DA_I8_READ,VTK_VAR_XML_SCAL_3DA_I8_READ, & ! integer(I8P) scalar    1D/3D array
                     VTK_VAR_XML_SCAL_1DA_I4_READ,VTK_VAR_XML_SCAL_3DA_I4_READ, & ! integer(I4P) scalar    1D/3D array
                     VTK_VAR_XML_SCAL_1DA_I2_READ,VTK_VAR_XML_SCAL_3DA_I2_READ, & ! integer(I2P) scalar    1D/3D array
                     VTK_VAR_XML_SCAL_1DA_I1_READ,VTK_VAR_XML_SCAL_3DA_I1_READ, & ! integer(I1P) scalar    1D/3D array
                     VTK_VAR_XML_VECT_1DA_R8_READ,VTK_VAR_XML_VECT_3DA_R8_READ, & ! real(R8P)    vectorial 1D/3D arrays
                     VTK_VAR_XML_VECT_1DA_R4_READ,VTK_VAR_XML_VECT_3DA_R4_READ, & ! real(R4P)    vectorial 1D/3D arrays
                     VTK_VAR_XML_VECT_1DA_I8_READ,VTK_VAR_XML_VECT_3DA_I8_READ, & ! integer(I8P) vectorial 1D/3D arrays
                     VTK_VAR_XML_VECT_1DA_I4_READ,VTK_VAR_XML_VECT_3DA_I4_READ, & ! integer(I4P) vectorial 1D/3D arrays
                     VTK_VAR_XML_VECT_1DA_I2_READ,VTK_VAR_XML_VECT_3DA_I2_READ, & ! integer(I2P) vectorial 1D/3D arrays
                     VTK_VAR_XML_VECT_1DA_I1_READ,VTK_VAR_XML_VECT_3DA_I1_READ, & ! integer(I1P) vectorial 1D/3D arrays
                     VTK_VAR_XML_LIST_1DA_R8_READ,VTK_VAR_XML_LIST_3DA_R8_READ, & ! real(R8P)    list      1D/3D array
                     VTK_VAR_XML_LIST_1DA_R4_READ,VTK_VAR_XML_LIST_3DA_R4_READ, & ! real(R4P)    list      1D/3D array
                     VTK_VAR_XML_LIST_1DA_I8_READ,VTK_VAR_XML_LIST_3DA_I8_READ, & ! integer(I4P) list      1D/3D array
                     VTK_VAR_XML_LIST_1DA_I4_READ,VTK_VAR_XML_LIST_3DA_I4_READ, & ! integer(I4P) list      1D/3D array
                     VTK_VAR_XML_LIST_1DA_I2_READ,VTK_VAR_XML_LIST_3DA_I2_READ, & ! integer(I2P) list      1D/3D array
                     VTK_VAR_XML_LIST_1DA_I1_READ,VTK_VAR_XML_LIST_3DA_I1_READ    ! integer(I1P) list      1D/3D array
  endinterface
  
  !-----------------------------------------------------------------------------------------------------------------------------------
  