Re: SwingWorker like interface in glib main loop?

["DANIELLLANO terra es" <DANIELLLANO terra es>]

Chris Vine wrote:
> On Mon, 8 Sep 2008 23:16:44 +0200 (MEST)
> "DANIELLLANO terra es" <DANIELLLANO terra es> wrote:
> > I just saw Havoc's blog entry "SYNCHRONOUS IO NEVER OK":
> > http://log.ometer.com/2008-09.html#7
> > 
> > and I wondered if there is a
> > http://en.wikipedia.org/wiki/SwingWorker
> > like interface in glib to run blocking code outside the glib main loop
> > to prevent locking the gtk+ GUI?
> > 
> > Do you guys know an easy solution like SwingWorker for glib?
> 
> You can do non-blocking reads and writes with GIOChannel without having
> to start any new threads and it is not much more difficult than
> blocking reads - you set it non-blocking with g_io_channel_set_flags(),
> plumb it into the main loop with g_io_add_watch() and read whatever
> happens to be available in your callback function (until you get
> G_IO_STATUS_AGAIN returned on the iochannel read), and keep on doing
> that until you reach end of file or you have obtained whatever you were
> expecting.  At that point you can remove the watch.

The problem is that open() does not have a non-blocking equivalent and
when I want to open a NFS file over a slow connection my GUI can block
for a long time. So I need to do the open() in another thread anyway.
There are lots of other blocking functions in the kernel that do not have
a non-blocking equivalent.

> However, if you really need blocking reads (not very likely), you can
> start a new thread to do the work - see:
> 
> http://library.gnome.org/devel/glib/stable/glib-Threads.html
> 
> You can hand any result back to the main GUI thread with g_idle_add()
> (g_idle_add() is thread safe).

I would like to have a extremely simple API in glib for doing this
kind of blocking calls as easily as possible.
Do you guys think a simple API like SwingWorker could be integrated in glib?



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