Re: AW: Is Disptacher-functionality Gtkmm only?

[Chris Vine <chris cvine freeserve co uk>]

On Sunday 01 January 2006 08:20, Daniel Kraft wrote:
> Hi!
>
> > On Saturday 31 December 2005 15:51, Daniel Kraft wrote:
> > > Hi!
> > >
> > > My system seems to have some problems with idle signals and the
> > > Dispatcher class (as I priviously posted); therefore I used pure GTK+
> > > for idle signals, and it worked.
> > >
> > > Now I wanted to try the same for Dispatcher, but I couldn't find the
> > > GTK+ equivalent! Is that a Gtkmm-added feature? If so, has anyone an
> > > idea how to do the same in GTK+ (although this is the wrong mailing
> > > list)?
> >
> > Glib::Dispatcher doesn't use idle signals.  It uses a pipe to communicate
> > between threads.  It is specific to glibmm (it does not have an
> > equivalent in glib), but you can easily make your own with a pipe and a
> > GIOChannel object. If you have a problem with Glib::Dispatcher, it is
> > almost certainly a coding error in your code and not a problem with
> > either glibmm or your "system".
>
> My original problem was really that my Gtkmm-installation didn't work
> correctly (as I use Cygwin, which seems to be a bit unusual system) - even
> the Dispatcher examples were broken.
>
> Thank you for your solution! I think this should work for me.

Oh, I see.  If you want a glib-based (not glibmm) C++ solution you could try:

http://cvs.sourceforge.net/viewcvs.py/efax-gtk/efax-gtk/src/utils/notifier.h?rev=1.6
http://cvs.sourceforge.net/viewcvs.py/efax-gtk/efax-gtk/src/utils/notifier.cpp?rev=1.4

And to make sense of the code you would also need this pipe wrapper (but you 
could easily modify the code not to use the wrapper):

http://cvs.sourceforge.net/viewcvs.py/efax-gtk/efax-gtk/src/utils/pipes.h?rev=1.5
http://cvs.sourceforge.net/viewcvs.py/efax-gtk/efax-gtk/src/utils/pipes.cpp?rev=1.2

and also, unless you were to modify the code to use a GIOChannel object rather 
than a slightly lower overhead custom GSource object, these:

http://cvs.sourceforge.net/viewcvs.py/efax-gtk/efax-gtk/src/utils/io_watch.h?rev=1.3
http://cvs.sourceforge.net/viewcvs.py/efax-gtk/efax-gtk/src/utils/io_watch.cpp?rev=1.2

This code also uses libsigc++ for the callback, but you could use a simple 
function object or indeed a function pointer instead for the callback if 
wanted.  (I imagine however that you can compile libsigc++ OK as the 
libsigc++ documentation says that it works with both cygwin and .NET 2003.)  
The code also uses a pthread-based mutex to ensure atomicity between threads 
writing to the (single) notifier pipe, for which you can substitute the glib 
GThread mutex.

Anyway, this might give you some ideas.

Chris