EXEC_BACKEND

We keep talking about EXEC_BACKEND mode, though until recently I had
misunderstood what that meant. I also realised that I have more than
once neglected to take it into account when writing a patch - one recent
patch failed to do this.

I can't find anything coherent in docs/readme/comments to explain why it
exists and what its implications are. The why is "Windows", AFAICS, but
the full implications are far from clear in my blissful, mostly
Window-less world.

Can someone either point me to or write a coherent explanation of this,
so that we can add it to the code somewhere handy? I want to make sure
that everything I'm working on covers the main points the first time I
wrote code.

Thanks,

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support