Re: small typo in src/backend/access/transam/xlog.c

On Mon, Jul 22, 2013 at 6:45 AM, didier <did447@gmail.com> wrote:
> Hi
>
> in void
> BootStrapXLOG(void)
>
>       * to seed it other than the system clock value...)  The upper half of
> the
>          * uint64 value is just the tv_sec part, while the lower half is the
> XOR
>          * of tv_sec and tv_usec.  This is to ensure that we don't lose
> uniqueness
>          * unnecessarily if "uint64" is really only 32 bits wide.  A person
>          * knowing this encoding can determine the initialization time of
> the
>          * installation, which could perhaps be useful sometimes.
>          */
>         gettimeofday(&tv, NULL);
>         sysidentifier = ((uint64) tv.tv_sec) << 32;
>         sysidentifier |= (uint32) (tv.tv_sec | tv.tv_usec);
>
> should be
>         sysidentifier |= (uint32) (tv.tv_sec ^ tv.tv_usec);

And why is that?

-- 
Robert Haas
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