Virtual Method
GioInitableinit
since: 2.22
Declaration [src]
gboolean
init (
GInitable* initable,
GCancellable* cancellable,
GError** error
)
Description [src]
Initializes the object implementing the interface.
This method is intended for language bindings. If writing in C,
g_initable_new() should typically be used instead.
The object must be initialized before any real use after initial construction, either with this function or g_async_initable_init_async().
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
G_IO_ERROR_CANCELLED will be returned. If cancellable is not NULL and
the object doesn’t support cancellable initialization the error
G_IO_ERROR_NOT_SUPPORTED will be returned.
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. 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 g_initable_init()
on the result of g_object_new(), regardless of whether it is in fact a new instance.
Available since: 2.22
Parameters
cancellable-
Type:
GCancellableOptional
GCancellableobject,NULLto ignore.The argument can be NULL.The data is owned by the caller of the method. error-
Type:
GError **The return location for a recoverable error.
The argument can be NULL.If the return location is not NULL, then you must initialize it to aNULLGError*.The argument will be left initialized to NULLby the virtual function if there are no errors.In case of error, the argument will be set to a newly allocated GError; the caller will take ownership of the data, and be responsible for freeing it.