read_config_from_string Subroutine

   subroutine read_config_from_string(text, cfg, schema, ierr)
      !! In-memory sibling of [[read_config]]: build + strict-parse +
      !! apply a namelist held entirely in the `text` buffer (newline-
      !! separated), with NO filesystem touch — no temp file, no `chdir`,
      !! no cleanup.  Same validation behaviour as the file path (the
      !! schema parser and the native &ocean_bc_nml read both run from
      !! the in-memory line array); same `error stop` default and same
      !! optional non-aborting `ierr` as [[read_config]].
      character(len=*), intent(in) :: text
         !! Whole namelist as one string (records separated by '\n').
      type(config_t), target, intent(out) :: cfg
      type(nml_schema_t), intent(out), optional :: schema
      integer, intent(out), optional :: ierr
         !! Non-zero on a strict-parse failure when present; absent
         !! behaves as today (`error stop`). The natural FFI/create()
         !! door: a bad namelist string becomes a returned status
         !! instead of aborting the host process.

      if (present(schema)) then
         call read_config_from_string_impl(text, cfg, schema, ierr=ierr)
      else
         block
            type(nml_schema_t) :: sch
            call read_config_from_string_impl(text, cfg, sch, ierr=ierr)
         end block
      end if
   end subroutine read_config_from_string