Re: Libpq PGRES_COPY_BOTH - version compatibility

I wrote:
> Now if we had a track record showing that we could tweak the protocol
> version without causing problems, it'd be fine with me to do it for this
> usage.  But we don't, and this particular case doesn't seem like the
> place to start.

And, btw, a moment's study of the protocol version checking code in
postmaster.c shows that bumping the minor version number to 3.1 *would*
break things: a client requesting 3.1 from a current postmaster would
get a failure.

Maybe we oughta change that logic --- it's not clear to me that there's
any meaningful difference between major and minor numbers given the
current postmaster behavior.
        regards, tom lane