psql - pager support - using invisible chars for signalling end of report

Hi

Last release of pspg supports stream mode - it means so you can open psql
in one terminal, redirect output to named pipe. In second terminal you can
start pspg and read input from named pipe. Then you can see and edit SQL in
one terminal, and you can see a result in second terminal.

It is working very well, but it is not too robust how I would. I miss a
some message in communication that can ensure synchronization - some
special char that can be used as separator between two results. Now, it is
based on detection and evaluation positions of empty rows.

I had a idea using some invisible chars, that are usually ignored (and use
these special characters only when user would it).

There are possible characters:

03 ETX .. end of text
28 FS .. file separator
29 GS .. group separator

What do you think about this?

Regards

Pavel