OT: klipper's misbeliefs [was: NEdit & KDE loss of selection problems]

[Joerg Fischer]

I think I did some progress with the klipper folks in the sense that
they don't consider the bug report as invalid now.  I presume this is
because klipper doesn't intend to take the primary if there is already
a non-zero primary on the screen.

http://bugs.kde.org/show_bug.cgi?id=129994

I proposed the following: Since it only matters what is in the
clipboard[1] when the user says 'paste it', it isn't necessary to
avoid an empty clipboard[2] every time the clipboard gets empty.
Therefore prevent the clipboard from being empty only when there is a
middle-click event, ie, set the clipboard only at this time, which is
also safe because *then* the user just likes to paste the clipboard
and isn't in the middle of doing anything else (one would possibly
interfere with).

Now, they say this wouldn't work, and I can't know.  I see that
klipper itself couldn't grab middle-click events, but klipper is part
of KDE and I believe KDE as desktop or window manager could get X
events before anyone else sees them.  Is this right?


In any case, all what nedit could do I think would be to keep owning
empty selections, if it is certain that this doesn't break anything.
Notice though that in this case the "prevent empty clipboard" option
simply wouldn't work for nedit, since klipper wouldn't detect any
selection inside nedit but the very first one - it watches only for
changes in ownership and nedit would just go on owning the
selection(s).  So the selection can be empty in nedit, but klipper
doesn't notice and therefore doesn't take the selection.

The next thing we or I should do is to write an essay about it for
Niki, because I don't believe the klipper folks - due to their
(mis)understanding of selection/clipboard - aren't able to write a
proper documentation of this, so that anyone running into this would
have any chances but good luck to figure out what goes on. 


Cheers,
Jörg




[1] For the klipper folks or at least some of them this "is
    simply a lazy way to name both/either of them [the PRIMARY
    selection and the CLIPBOARD selection]", while all of them
    "are well aware of the differences, whatever you [me] might
    think" - so, after all me tried to explain, I think me is out
    of the discussion at this point.
    
[2] Just in case you don't happen to be such fully aware about
    the differences between clipboard and selection as the
    klipper folks, you must replace clipboard with (PRIMARY)
    selection eacht time to understand the text.