[Plplot-general] Error using threads, GTK and Cairo driver

[Johan M. <joh...@gm...>]

Hi
I am trying to display several curves with updates in real time of the
displayed values. In order to do this, I launch my main window with
GTK/Cairo/PLplot in the main program and a thread that generate the values
to be displayed.
All of this being coded in Ocaml through dedicated bindings.

Each time that I need to change a curve from the thread, I reinitialize the
plplot stream and create a new one with new values.
However, since I am using Cairo driver inside GTK, the generated graphs and
window are also affected by GTK handler launched by signals that redraws the
widget and thus the curves.

And unfortunately, some of these handler sometime launch at the same time as
I am modifying some curves. This produces an error because some plplot
stream are affected by commands in the wrong order (commands from the redraw
in the handler and from the function to redraw curves with new values).
I tried to avoid this by the use of mutexes that forbids the use of some
function from both the main window with GTK/Cairo/PLplot and from the
thread.
However, this is not working.

My guess is that GTK and its Ocaml bindings, lablgtk, are handling threads
and mutexes in a special way.
But my knowledge on this point is very sparse. And it would be very helpful
if someone could help me on this point.

Thanks in advance for your time.

Regards.
Johan Mazel