MainContext.wakeup

If context is currently blocking in glib.main_context.MainContext.iteration waiting for a source to become ready, cause it to stop blocking and return. Otherwise, cause the next invocation of glib.main_context.MainContext.iteration to return without blocking.

This API is useful for low-level control over #GMainContext; for example, integrating it with main loop implementations such as #GMainLoop.

Another related use for this function is when implementing a main loop with a termination condition, computed from multiple threads:

#define NUM_TASKS 10
static gint tasks_remaining = NUM_TASKS;  // (atomic)
...

while (g_atomic_int_get (&tasks_remaining) != 0)
  g_main_context_iteration (NULL, TRUE);

Then in a thread:

perform_work();

if (g_atomic_int_dec_and_test (&tasks_remaining))
  g_main_context_wakeup (NULL);