Unable to get response after method call

[Asif_Bahrainwala]

In continuation of : Sample code to capture screen to memory (raw image) in Wayland - #12 by skeller

Please refer to my code in the above link

The code works fine. If i add a sleep(5) after calling Screenshot method, I do not get the response. If I subscribe to the signal , then every thing works fine.

Is there a requirement to get the response (via g_dbus_proxy_new_for_bus_sync) within a certain amount time/race condition?

GVariant *retval=g_dbus_proxy_call_sync (proxy, “Screenshot”, g_variant_new (“(sa{sv})”,“”,options, NULL),G_DBUS_CALL_FLAGS_NONE,-1, NULL, &error);

sleep(5); //this causes the problem

if (retval)
{

    //now to get the request
    gchar *opath         = NULL;
    g_variant_get (retval, "(o)", &opath);
    auto proxy2 = g_dbus_proxy_new_for_bus_sync (G_BUS_TYPE_SESSION,
                                                G_DBUS_PROXY_FLAGS_NONE,
                                                NULL,
                                                "org.freedesktop.portal.Desktop",
                                                opath,
                                                "org.freedesktop.portal.Request",
                                                NULL, NULL);


    g_signal_connect (proxy2, "g-signal",
                     G_CALLBACK (screenshot_freedesktop_dbus_signal),
                     nullptr);

the method for this signal is never called (because of the sleep added earlier)
...

[Asif_Bahrainwala]

Looking at Request - XDG Desktop Portal documentation

They do discuss a certain race condition, could any one elaborate on this, thanks

PS my code has been picked up from GIMP source code