[Gnuplot-info] Weird behaviour of qt and wxt terminals regarding closing of standard output

[Thomas O. <tho...@or...>]

Note: Sending this a third time now ... as I gather that the other attempts failed to reach the list (am I being filtered out as spam?).

Hi,

I have a long-standing problem with gnuplot's newer graphical
terminals, first the wxt one, now the qt one showing the same.
I brought this up on IRC some time ago, but without much success ...
and I admit that I tried to ignore the issue by defaulting to the x11
terminal. But, well, since this is spreading into the qt terminal, too,
I really would like to see the pattern investigated and fixed.

This is gnuplot 4.6 currently.

The issue can be reduced to this (on GNU/Linux):

shell$ echo 'set term x11; plot x' | gnuplot -persist | cat
shell$

That opens a x11 plot window which stays there and exits, giving me my
shell prompt back. But this,

shell$ echo 'set term qt; plot x' | gnuplot -persist | cat

just hangs there. Why is the terminal type making a difference here?
Gnuplot's input is closed ... why does it not close the output side?
And yes, I am aware that dropping the '| cat' would fix the behaviour,
but that would be missing the point as this is a very reduced example
for a wrapper script that wants to hook something on gnuplot's text
output.


Alrighty then,

Thomas


PS: The qt terminal has fuzzy icons ... looks bad compared to the wxt
one (which looks more complete anyway). But well, I prefer the simple
x11 windows anyhow. And please, if they are about to be dropped in
favour of qt, please add an option to remove any widgets, having only
the plotting area remain.