Synopsis#include <gio/gio.h> GAsyncResult; GAsyncResultIface; void (*GAsyncReadyCallback) (GObject *source_object, GAsyncResult *res, gpointer user_data); gpointer g_async_result_get_user_data (GAsyncResult *res); GObject* g_async_result_get_source_object (GAsyncResult *res); DescriptionProvides a base class for implementing asynchronous function results.
Asynchronous operations are broken up into two separate operations
which are chained together by a GAsyncReadyCallback. To begin
an asynchronous operation, provide a GAsyncReadyCallback to the
asynchronous function. This callback will be triggered when the
operation has completed, and will be passed a GAsyncResult instance
filled with the details of the operation's success or failure, the
object the asynchronous function was started for and any error codes
returned. The asynchronous callback function is then expected to call
the corresponding "
The purpose of the " Example of a typical asynchronous operation flow: void _theoretical_frobnitz_async (Theoretical *t, GCancellable *c, GAsyncReadyCallback *cb, gpointer u); gboolean _theoretical_frobnitz_finish (Theoretical *t, GAsyncResult *res, GError **e); static void frobnitz_result_func (GObject *source_object, GAsyncResult *res, gpointer user_data) { gboolean success = FALSE; success = _theoretical_frobnitz_finish (source_object, res, NULL); if (success) g_printf ("Hurray!\n"); else g_printf ("Uh oh!\n"); /* ... */ } int main (int argc, void *argv[]) { /* ... */ _theoretical_frobnitz_async (theoretical_data, NULL, frobnitz_result_func, NULL); /* ... */ }
The callback for an asynchronous operation is called only once, and is
always called, even in the case of a cancelled operation. On cancellation
the result is a Some ascynchronous operations are implemented using synchronous calls. These are run in a separate thread, if GThread has been initialized, but otherwise they are sent to the Main Event Loop and processed in an idle function. So, if you truly need asynchronous operations, make sure to initialize GThread.
DetailsGAsyncResulttypedef struct _GAsyncResult GAsyncResult;
Holds results information for an asynchronous operation,
usually passed directly to a asynchronous
GAsyncResultIfacetypedef struct { GTypeInterface g_iface; /* Virtual Table */ gpointer (* get_user_data) (GAsyncResult *async_result); GObject * (* get_source_object) (GAsyncResult *async_result); } GAsyncResultIface; Interface definition for GAsyncResult.
GAsyncReadyCallback ()void (*GAsyncReadyCallback) (GObject *source_object, GAsyncResult *res, gpointer user_data); Type definition for a function that will be called back when an asynchronous operation within GIO has been completed.
g_async_result_get_user_data ()gpointer g_async_result_get_user_data (GAsyncResult *res); Gets the user data from a GAsyncResult.
g_async_result_get_source_object ()GObject* g_async_result_get_source_object (GAsyncResult *res); Gets the source object from a GAsyncResult.
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