GInitable is implemented by objects that can fail during
initialization. If an object implements this interface then
it must be initialized as the first thing after construction,
either via g_initable_init() or g_async_initable_init_async()
(the latter is only available if it also implements GAsyncInitable).
If the object is not initialized, or initialization returns with an
error, then all operations on the object except g_object_ref() and
g_object_unref() are considered to be invalid, and have undefined
behaviour. They will often fail with g_critical() or g_warning(), but
this must not be relied on.
Users of objects implementing this are not intended to use
the interface method directly, instead it will be used automatically
in various ways. For C applications you generally just call
g_initable_new() directly, or indirectly via a foo_thing_new() wrapper.
This will call g_initable_init() under the cover, returning NULL and
setting a GError on failure (at which point the instance is
unreferenced).
For bindings in languages where the native constructor supports
exceptions the binding could check for objects implemention GInitable
during normal construction and automatically initialize them, throwing
an exception on failure.
GInitable is implemented by objects that can fail during initialization. If an object implements this interface then it must be initialized as the first thing after construction, either via g_initable_init() or g_async_initable_init_async() (the latter is only available if it also implements GAsyncInitable).
If the object is not initialized, or initialization returns with an error, then all operations on the object except g_object_ref() and g_object_unref() are considered to be invalid, and have undefined behaviour. They will often fail with g_critical() or g_warning(), but this must not be relied on.
Users of objects implementing this are not intended to use the interface method directly, instead it will be used automatically in various ways. For C applications you generally just call g_initable_new() directly, or indirectly via a foo_thing_new() wrapper. This will call g_initable_init() under the cover, returning NULL and setting a GError on failure (at which point the instance is unreferenced).
For bindings in languages where the native constructor supports exceptions the binding could check for objects implemention GInitable during normal construction and automatically initialize them, throwing an exception on failure.