pg_dump/pg_restore: Fix stdin/stdout handling of custom format on Win32

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pg_dump/pg_restore: Fix stdin/stdout handling of custom format on Win32 ×

First at 2022-12-16 15:09:21 by Daniel Watzinger <daniel.watzinger at gmail.com>
Latest at 2023-03-15 03:58:28 by Michael Paquier <michael at paquier.xyz>
Latest attachment (v2-0002-improve-detection-file-type-for-WIN32-stat.patch) at 2023-03-09 23:12:37 from Juan José Santamaría Flecha <juanjo.santamaria at gmail.com>

    Attachment (v2-0002-improve-detection-file-type-for-WIN32-stat.patch) at 2023-03-09 23:12:37 from Juan José Santamaría Flecha <juanjo.santamaria at gmail.com> (Patch: Yes)
    Attachment (v1-0001-pg_dump-pg_restore-Fix-stdin-stdout-handling-of-c.patch) at 2022-12-16 23:55:24 from Daniel Watzinger <daniel.watzinger at gmail.com> (Patch: Yes)
    Attachment (v1-0001-pg_dump-pg_restore-Fix-stdin-stdout-handling-of-c.patch) at 2022-12-16 15:09:21 from Daniel Watzinger <daniel.watzinger at gmail.com> (Patch: No)

Fix fseek() detection of unseekable files on WIN32 ×

First at 2023-03-14 12:26:27 by Juan José Santamaría Flecha <juanjo.santamaria at gmail.com>
Latest at 2023-04-12 02:19:52 by Michael Paquier <michael at paquier.xyz>
Latest attachment (v4-0001-fix-fseek-detection-of-unseekable-files-for-WIN32.patch) at 2023-04-11 05:43:25 from Michael Paquier <michael at paquier.xyz>

    Attachment (v4-0001-fix-fseek-detection-of-unseekable-files-for-WIN32.patch) at 2023-04-11 05:43:25 from Michael Paquier <michael at paquier.xyz> (Patch: Yes)
    Attachment (v3-0001-fix-fseek-detection-of-unseekable-files-for-WIN32.patch) at 2023-03-19 11:45:00 from Michael Paquier <michael at paquier.xyz> (Patch: Yes)
    Attachment (v2-0001-fix-fseek-detection-of-unseekable-files-for-WIN32.patch) at 2023-03-15 11:18:25 from Juan José Santamaría Flecha <juanjo.santamaria at gmail.com> (Patch: Yes)
    Attachment (0001-fix-fseek-detection-of-unseekable-files-for-WIN32.patch) at 2023-03-14 12:26:27 from Juan José Santamaría Flecha <juanjo.santamaria at gmail.com> (Patch: Yes)