Initable.init_

Initializes the object implementing the interface.

This method is intended for language bindings. If writing in C, [gio.initable.Initable.new_] should typically be used instead.

The object must be initialized before any real use after initial construction, either with this function or [gio.async_initable.AsyncInitable.initAsync].

Implementations may also support cancellation. If cancellable is not null, then initialization can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error [gio.types.IOErrorEnum.Cancelled] will be returned. If cancellable is not null and the object doesn't support cancellable initialization the error [gio.types.IOErrorEnum.NotSupported] will be returned.

If the object is not initialized, or initialization returns with an error, then all operations on the object except [gobject.object.ObjectWrap.ref_] and [gobject.object.ObjectWrap.unref] are considered to be invalid, and have undefined behaviour. See the [introduction][ginitable] for more details.

Callers should not assume that a class which implements #GInitable can be initialized multiple times, unless the class explicitly documents itself as supporting this. Generally, a class’ implementation of init() can assume (and assert) that it will only be called once. Previously, this documentation recommended all #GInitable implementations should be idempotent; that recommendation was relaxed in GLib 2.54.

If a class explicitly supports being initialized multiple times, it is recommended that the method is idempotent: multiple calls with the same arguments should return the same results. Only the first call initializes the object; further calls return the result of the first call.

One reason why a class might need to support idempotent initialization is if it is designed to be used via the singleton pattern, with a #GObjectClass.constructor that sometimes returns an existing instance. In this pattern, a caller would expect to be able to call [gio.initable.Initable.init_] on the result of [gobject.object.ObjectWrap.new_], regardless of whether it is in fact a new instance.