ReadInputMain Subroutine

    Subroutine ReadInputMain(cFilename, tOverride_input, kp)
        use SystemData, only: tMolpro
        use System, only: SysReadInput, SetSysDefaults
        use Calc, only: CalcReadInput, SetCalcDefaults
        use CalcData, only: tKP_FCIQMC, tUseProcsAsNodes
        use kp_fciqmc_data_mod, only: kp_fciqmc_data
        use kp_fciqmc_init, only: kp_fciqmc_read_inp
        use Integrals_neci, only: IntReadInput, SetIntDefaults
        Use Logging, only: LogReadInput, SetLogDefaults
        use Parallel_neci, only: iProcIndex
        use default_sets
        use util_mod, only: get_free_unit
        use real_time_read_input_module, only: real_time_read_input
!#ifdef NAGF95
!    !  USe doesn't get picked up by the make scripts
!        USe f90_unix_env, ONLY: getarg,iargc
!#endif
        Implicit none
!#ifndef NAGF95
!        Integer :: iargc
!#endif
        !  INPUT/OUTPUT params
        character(*), parameter :: this_routine = 'ReadInputMain'
        Character(len=*) cFilename    !Input  filename or "" if we check arg list or stdin

        Character(len=255) cInp         !temp storage for command line params
        Character(len=32) cTitle
!  Predeclared
        Character(len=100) w, x         !strings for input storage
        Logical tEof        !set when read_line runs out of lines
        logical tExists     !test for existence of input file.
        Integer idDef       !What default set do we use
        integer neci_iargc
        logical, intent(in) :: tOverride_input  !If running through molpro, is this an override input?
        integer, allocatable :: tmparr(:)
        type(kp_fciqmc_data), intent(inout) :: kp
        integer, parameter :: id_scratch_file = 7
        class(FileReader_t), allocatable :: file_reader
        type(TokenIterator_t) :: tokens

        cTitle = ""
        idDef = idDefault                 !use the Default defaults (pre feb08)
        If (trim(adjustl(cFilename)) /= '') Then
            file_reader = ManagingFileReader_t(trim(adjustl(cFilename)))
        else if (neci_iArgC() > 0) then
            ! We have some arguments we can process instead
#ifdef BLUEGENE_HACKS
            call neci_GetArg(neci_iArgC(), cInp)
#else
            Call neci_GetArg(1, cInp)      !Read argument 1 into inp
#endif
            write(stdout, *) "Processing arguments", cinp
            write(stdout, *) "Reading from file: ", Trim(cInp)
            file_reader = ManagingFileReader_t(trim(adjustl(cInp)))
        Else
            write(stdout, *) "Reading from STDIN"
            ! Save the input to a temporary file so we can scan for the
            ! defaults option and then re-read it for all other options.
            open(id_scratch_file, status='scratch')
            file_reader = AttachedFileReader_t(file_id=stdin, echo_lines=id_scratch_file)
        end if

        Do while (file_reader%nextline(tokens, skip_empty=.true.))
            w = to_upper(tokens%next())
            Select case (w)
            Case ("DEFAULTS")
                x = to_upper(tokens%next())
                select case (x)
!Add default options here
                case ("DEFAULT")
                    idDef = idDefault
                case ("FEB08")
                    idDef = idFeb08
                case ("NOV11")
                    idDef = idNov11
                case default
                    write(stdout, *) "No defaults selected - using 'default' defaults"
                    idDef = idDefault
                end select
            case ("END")
                exit
            end select
        End Do

        select case (idDef)
        case (0)
            write(stdout, *) 'Using the default set of defaults.'
        case (idFeb08)
            Feb08 = .true.
            write(stdout, *) 'Using the Feb08 set of defaults.'
        case (idNov11)
            Nov11 = .true.
            write(stdout, *) 'Using the November 2011 set of defaults'
        end select

        ! Set up defaults.
        call SetSysDefaults
        call SetCalcDefaults
        call SetIntDefaults
        call SetLogDefaults

        ! Now return to the beginning and process the whole input file
        select type(file_reader)
        type is (AttachedFileReader_t)
            file_reader = AttachedFileReader_t(file_id=id_scratch_file)
        end select

        call file_reader%rewind()

!Molpro writes out its own input file
        if (.not. tMolpro .or. tOverride_input) then
            if (iProcIndex == 0) then
                call file_reader%set_echo_lines(stdout)
            else
                call file_reader%set_echo_lines()
            end if
            write(stdout, '(/,64("*"),/)')
        end if

        Do while (file_reader%nextline(tokens, skip_empty=.true.))
            w = to_upper(tokens%next())
            select case (w)
            case ("TITLE")
                do while (tokens%remaining_items() > 0)
                    w = tokens%next()
                    cTitle = trim(cTitle)//" "//trim(w)
                end do
            case ("DEFAULTS")
                CONTINUE
            case ("SYSTEM")
                call SysReadInput(file_reader, tokens)
            case ("CALC")
                call CalcReadInput(file_reader)
            case ("INTEGRAL")
                call IntReadInput(file_reader)
            case ("LOGGING")
                call LogReadInput(file_reader)
            case ("KP-FCIQMC")
                tKP_FCIQMC = .true.
                tUseProcsAsNodes = .true.
                call kp_fciqmc_read_inp(file_reader, kp)
            case ("REALTIME")
                call real_time_read_input(file_reader)
            case ("END")
                exit
            case default
                call stop_all(this_routine, "Keyword "//trim(w)//" not recognized")
            end select
        end do
        write(stdout, '(/,64("*"),/)')
        call file_reader%close()
        call sanitize_input()
        RETURN
    END SUBROUTINE ReadInputMain