J3/06-317r3 Date: 16 November 2006 To: J3 From: Aleksandar Donev Subject: Issues 42 & 43, teams for preconnected units Reference: J3/06-007r1, J3/06-258, J3/06-338r1 Discussion of issues 42 and 43 (page 220) The intention is not to affect the behaviour on image 1 of preconnected units and the units INPUT_UNIT, OUTPUT_UNIT, ERROR_UNIT, but to limit their use on other images to simple output. The main mechanism for parallel i/o is the direct-access file, connected through an OPEN statement. We agree that the present wording is overly restrictive, and that the connect team for INPUT_UNIT should be image 1. While discussing this paper we realized that the description of the CLOSE statement did not explain that it causes team synchronization. This was only explained in the description of SYNC TEAM. If some of the images have initiated termination, the implicit synchronization implied by the CLOSE statement for a unit with a connect team that has more than one image (8.5.3) will fail. The IOSTAT variable can be used to catch the error there, or, if there isn't one, abnormal termination will occur. This is addressed in 06-338r1. Edits to J3/06-007r1 [220:7-10] Replace the last paragraph of 9.4.5.17 TEAM= specifier: "Units connected to a preconnected file, other than the unit identified by the value INPUT_UNIT in the intrinsic module ISO_FORTRAN_ENV have a connect team consisting of all the images. The unit identified by the value INPUT_UNIT in the intrinsic module ISO_FORTRAN_ENV is preconnected with a connect team consisting of image 1 on image 1 and is not preconnected on other images." [220:10+] Add a new sentence to the end of Note 9.24: "File positioning statements and READ are not allowed for preconnected units, including units preconnected to OUTPUT_UNIT and ERROR_UNIT, if the number of images is greater than one. The FLUSH and INQUIRE statements are always allowed for preconnected units." [221:17+] Add a new paragraph "If an image executes a CLOSE statement, all images in the connect team of the unit specified shall execute a CLOSE statement for the unit with the same status. There is an implicit team synchronization associated with the execution of a CLOSE statement for a unit with a connect team that has more than one image (8.5.3)."