Re: [GENERAL] pg_upgrade from 9.5 to 9.6 fails with "invalid argument"

On Fri, Sep 30, 2016 at 7:08 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
>> Tom Lane wrote:
>>> I wouldn't even put a lot of faith in the errno being meaningful,
>>> considering that it does close() calls before capturing the errno.
>
>> So we do close() in a bunch of places while closing shop, which calls
>> _close() on Windows; this function sets errno.
>
> But only on failure, no? The close()s usually shouldn't fail, and
> therefore shouldn't change errno, it's just that you can't trust that
> 100%.
>
> I think likely what's happening is that we're seeing a leftover value from
> some previous syscall that set GetLastError's result (and, presumably,
> wasn't fatal so far as pg_upgrade was concerned).
>

It means that read() syscall could not read BLOCKSZ bytes because
probably _vm file is corrupted?

> if ((src_fd = open(fromfile, O_RDONLY, 0)) < 0)

It could be happen that read() syscall stopped to read at where it
reads bits representing '\n' characters (0x5c6e) because we don't open
file with O_BINARY flag?

Regards,

--
Masahiko Sawada
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center