Yes, I have a tendency to use emacs sub-shells (and occasionally M-x
sql-postgres)--
I thought I'd reproduced the behavior in an xterm, but I was just
trying again and I don't see it. It does seem that the dumbness of my
dumb terminal is a factor.
If I understand the way this works, it could be an even more baffling
behavior if I were using an xterm: with a blank PAGER your output
would disappear only if the select exceeded a certain number of
lines...
On Wed, Dec 7, 2016 at 2:31 AM, Daniel Verite <daniel@manitou-mail.org> wrote:
> Tom Lane wrote:
>
>> BTW, I realized while testing this that there's still one gap in our
>> understanding of what went wrong for you: cases like "SELECT 'hello'"
>> should not have tried to use the pager, because that would've produced
>> less than a screenful of data
>
> At some point emacs was mentioned as the terminal:
>
>>> And I guess I did that intentionally, my .bashrc has
>>>
>>> # I use emacs shells, I got a "pager" already:
>>> export PAGER=''
>
> The M-x shell mode of emacs has a so-called "dumb" terminal
> emulation (that's the value of $TERM) where the notion of a "page"
> doesn't quite apply.
>
> For instance, when using emacs 24.3 with my default pager on an
> Ubuntu desktop, this is what I get:
>
> test=> select 1;
> WARNING: terminal is not fully functional
> - (press RETURN)
> ?column?
> ----------
> 1
> (1 row)
>
> I suspect that psql is unable to determine the screen size
> of the "dumb" terminal, and that it's the fault of the terminal
> rather than psql.
> The warning is displayed by "less" AFAICS.
>
> There are other psql features like tab-completion that don't work
> in this mode because emacs interpret keystrokes first for
> itself, in effect mixing emacs functionalities with these of the
> application run in the terminal. It's awesome sometimes
> and irritating at other times depending on what you expect :)
>
> OTOH it has also a M-x term command/mode that provides a
> more sophisticated screen emulation into which paging seems
> to work exactly like in a normal terminal and the emacs key bindings
> are turned off.
>
>
> Best regards,
> --
> Daniel Vérité
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> Twitter: @DanielVerite