Re: real/float example for testlibpq3

On 02/28/22 10:19, Tom Lane wrote:
>> That will standardize the
>> way to fetch real typed values in libpq. That leads to the next
>> question. Do we need to introduce different PQget*value() for standard
>> C/SQL data types.
> 
> ... I do not want to go here.  Where would you stop?  How would you
> deal with cross-machine inconsistencies in integer widths?

This stimulates a question for me.

Not just libpq, but all drivers implemented in whatever language, if they
wish to support binary protocol, depend on knowing what the committed
send/recv wire formats are for whichever types they mean to support.

In the current state of affairs, what's considered the ur-source of that
information?

I have often seen those formats documented in code comments, usually above
the recv function in the .c file for a given adt.

Have we got any more, well, machine-readable collection of that knowledge?

Regards,
-Chap