To:       J3                                                      07-302
From:     Jim Xia
Subject:  Interpretation: SIZE= specifier and UDDTIO

Date: 2007 October 15

NUMBER:   F03/
TITLE:    SIZE= specifier and UDDTIO
KEYWORDS: SIZE=, UDDTIO
DEFECT TYPE: Error
STATUS:   Erratum

DISCUSSION

9.5.1.14 [191:21-26] says that when SIZE= specifier is used in a
formatted input statement with explicit format specifications, the
variable specified in the SIZE= specifier is determined by the data edit
descriptors during the input statement.  These rules, however, did not
take into account of the following situation where a parent READ
statement with a DT edit descriptor invokes a user-defined DTIO formatted
read subroutine that reads input data using list-directed or namelist
READ statement.

Consider the following example,


module example
    type A
        integer x(10)

        contains

        procedure :: readArray
        generic :: read(formatted) => readArray
    end type

    contains

    subroutine readArray (dtv, unit, iotype, v_list, iostat, iomsg)
        class(A), intent(inout) :: dtv
        integer, intent(in) :: unit
        character(*), intent(in) :: iotype
        integer, intent(in) :: v_list(:)
        integer, intent(out) :: iostat
        character(*), intent(inout) :: iomsg

        read (unit, fmt=*, iostat=iostat, iomsg=iomsg) dtv%x
    end subroutine
end module

use example
    type(A) x
    integer countChar

    open (1, file='example.input', form='formatted')

    read (1, fmt='(DT)', advance='no', size=countChar) x
end


Note that there is no data edit descriptor in the UDDTIO subroutine,
readArray, to count the total number of characters transferred during
the child read.


QUESTION:

    (a) Is this example intended to be standard conforming?

    (b) If the answer to (a) is yes, then assume the file example.input
        contains the following text:
.1.2.3.4.5.6.7.8.9.10

        where each . represents a space. Then what value would the
        example assign to the variable countChar after the READ
        statement?

ANSWER:

    (a) No, this example is not standard conforming.

    (b) Not applicable.  SIZE= specifier is not allowed in the example
        presented here.  Edits are provided to correct this oversight.

EDITS:

    [188:8+] Append to the end of the paragraph

    "A SIZE= specifier shall not appear in a parent input statement if
     the user-defined derived-type input procedure to be invoked contains
     either a list-directed or a namelist input statement on the same
     input unit."


SUBMITTED BY: Jim Xia

HISTORY: m182 Submitted