Quoting Bruce Momjian <pgman@candle.pha.pa.us>:
> Mark Kirkwood wrote:
> > I was wondering about this point - might it not be just as reasonable
> > for the copied file to *be* an exact image of pg_control? Then a very
> > simple variant of pg_controldata (or maybe even just adding switches to
> > pg_controldata itself) would enable the relevant info to be extracted
>
> We didn't do that so admins could easily read the file contents.
>
Ease of reading is a good thing, no argument there.
However using 'pg_controldata' (or similar) to perform the read is not really
that much harder than using 'cat' - (it is a wee bit harder, I grant you)
When I posted the original mail I was thinking that the pg_control image is good
because it has much more information than just the last wal offset, and could
be used to perform a recovery in the advent of the "actual" pg_control being
unsuitable (e.g. backed up last instead of first on a busy system).
Of couse this thinking didn't make it into the original mail, sorry about that!
regards
Mark