Internal$signalsCompile-time signal type information.
This instance property is generated only for TypeScript type checking. It is not defined at runtime and should not be accessed in JS code.
Checks on the readiness of datagram_based to perform operations. The
operations specified in condition are checked for and masked against the
currently-satisfied conditions on datagram_based. The result is returned.
GObject.IOCondition.IN will be set in the return value if data is available to read with
g_datagram_based_receive_messages(), or if the connection is closed remotely
(EOS); and if the datagram_based has not been closed locally using some
implementation-specific method (such as g_socket_close() or
g_socket_shutdown() with shutdown_read set, if it’s a Gio.Socket).
If the connection is shut down or closed (by calling g_socket_close() or
g_socket_shutdown() with shutdown_read set, if it’s a Gio.Socket, for
example), all calls to this function will return Gio.IOErrorEnum.CLOSED.
GObject.IOCondition.OUT will be set if it is expected that at least one byte can be sent
using g_datagram_based_send_messages() without blocking. It will not be set
if the datagram_based has been closed locally.
GObject.IOCondition.HUP will be set if the connection has been closed locally.
GObject.IOCondition.ERR will be set if there was an asynchronous error in transmitting data
previously enqueued using g_datagram_based_send_messages().
Note that on Windows, it is possible for an operation to return
Gio.IOErrorEnum.WOULD_BLOCK even immediately after
g_datagram_based_condition_check() has claimed that the Gio.DatagramBased is
ready for writing. Rather than calling g_datagram_based_condition_check() and
then writing to the Gio.DatagramBased if it succeeds, it is generally better to
simply try writing right away, and try again later if the initial attempt
returns Gio.IOErrorEnum.WOULD_BLOCK.
It is meaningless to specify GObject.IOCondition.ERR or GObject.IOCondition.HUP in condition; these
conditions will always be set in the output if they are true. Apart from
these flags, the output is guaranteed to be masked by condition.
This call never blocks.
a GObject.IOCondition mask to check
the GObject.IOCondition mask of the current state
Waits for up to timeout microseconds for condition to become true on
datagram_based. If the condition is met, true is returned.
If cancellable is cancelled before the condition is met, or if timeout is
reached before the condition is met, then false is returned and error is
set appropriately (Gio.IOErrorEnum.CANCELLED or Gio.IOErrorEnum.TIMED_OUT).
a GObject.IOCondition mask to wait for
the maximum time (in microseconds) to wait, 0 to not block, or -1 to block indefinitely
Optionalcancellable: Gio.Cancellabletrue if the condition was met, false otherwise
Creates a GLib.Source that can be attached to a GLib.MainContext to monitor for
the availability of the specified condition on the Gio.DatagramBased. The
GLib.Source keeps a reference to the datagram_based.
The callback on the source is of the Gio.DatagramBasedSourceFunc type.
It is meaningless to specify GObject.IOCondition.ERR or GObject.IOCondition.HUP in condition; these
conditions will always be reported in the callback if they are true.
If non-null, cancellable can be used to cancel the source, which will
cause the source to trigger, reporting the current condition (which is
likely 0 unless cancellation happened at the same time as a condition
change). You can check for this in the callback using
g_cancellable_is_cancelled().
a GObject.IOCondition mask to monitor
Optionalcancellable: Gio.Cancellablea newly allocated GLib.Source
Receive one or more data messages from datagram_based in one go.
messages must point to an array of Gio.InputMessage structs and
num_messages must be the length of this array. Each Gio.InputMessage
contains a pointer to an array of Gio.InputVector structs describing the
buffers that the data received in each message will be written to.
flags modify how all messages are received. The commonly available
arguments for this are available in the Gio.SocketMsgFlags enum, but the
values there are the same as the system values, and the flags
are passed in as-is, so you can pass in system-specific flags too. These
flags affect the overall receive operation. Flags affecting individual
messages are returned in Gio.InputMessage.flags.
The other members of Gio.InputMessage are treated as described in its documentation.
If timeout is negative the call will block until num_messages have been
received, the connection is closed remotely (EOS), cancellable is cancelled,
or an error occurs.
If timeout is 0 the call will return up to num_messages without blocking,
or Gio.IOErrorEnum.WOULD_BLOCK if no messages are queued in the operating system
to be received.
If timeout is positive the call will block on the same conditions as if
timeout were negative. If the timeout is reached
before any messages are received, Gio.IOErrorEnum.TIMED_OUT is returned,
otherwise it will return the number of messages received before timing out.
(Note: This is effectively the behaviour of MSG_WAITFORONE with
recvmmsg().)
To be notified when messages are available, wait for the GObject.IOCondition.IN condition.
Note though that you may still receive Gio.IOErrorEnum.WOULD_BLOCK from
g_datagram_based_receive_messages() even if you were previously notified of a
GObject.IOCondition.IN condition.
If the remote peer closes the connection, any messages queued in the
underlying receive buffer will be returned, and subsequent calls to
g_datagram_based_receive_messages() will return 0 (with no error set).
If the connection is shut down or closed (by calling g_socket_close() or
g_socket_shutdown() with shutdown_read set, if it’s a Gio.Socket, for
example), all calls to this function will return Gio.IOErrorEnum.CLOSED.
On error -1 is returned and error is set accordingly. An error will only
be returned if zero messages could be received; otherwise the number of
messages successfully received before the error will be returned. If
cancellable is cancelled, Gio.IOErrorEnum.CANCELLED is returned as with any
other error.
an array of Gio.InputMessage structs
an int containing Gio.SocketMsgFlags flags for the overall operation
the maximum time (in microseconds) to wait, 0 to not block, or -1 to block indefinitely
Optionalcancellable: Gio.Cancellablea %GCancellable
number of messages received, or -1 on error. Note that the number of messages received may be smaller than num_messages if timeout is zero or positive, if the peer closed the connection, or if num_messages was larger than UIO_MAXIOV (1024), in which case the caller may re-try to receive the remaining messages.
Send one or more data messages from datagram_based in one go.
messages must point to an array of Gio.OutputMessage structs and
num_messages must be the length of this array. Each Gio.OutputMessage
contains an address to send the data to, and a pointer to an array of
Gio.OutputVector structs to describe the buffers that the data to be sent
for each message will be gathered from.
flags modify how the message is sent. The commonly available arguments
for this are available in the Gio.SocketMsgFlags enum, but the
values there are the same as the system values, and the flags
are passed in as-is, so you can pass in system-specific flags too.
The other members of Gio.OutputMessage are treated as described in its documentation.
If timeout is negative the call will block until num_messages have been
sent, cancellable is cancelled, or an error occurs.
If timeout is 0 the call will send up to num_messages without blocking,
or will return Gio.IOErrorEnum.WOULD_BLOCK if there is no space to send messages.
If timeout is positive the call will block on the same conditions as if
timeout were negative. If the timeout is reached before any messages are
sent, Gio.IOErrorEnum.TIMED_OUT is returned, otherwise it will return the number
of messages sent before timing out.
To be notified when messages can be sent, wait for the GObject.IOCondition.OUT condition.
Note though that you may still receive Gio.IOErrorEnum.WOULD_BLOCK from
g_datagram_based_send_messages() even if you were previously notified of a
GObject.IOCondition.OUT condition. (On Windows in particular, this is very common due to
the way the underlying APIs work.)
If the connection is shut down or closed (by calling g_socket_close() or
g_socket_shutdown() with shutdown_write set, if it’s a Gio.Socket, for
example), all calls to this function will return Gio.IOErrorEnum.CLOSED.
On error -1 is returned and error is set accordingly. An error will only
be returned if zero messages could be sent; otherwise the number of messages
successfully sent before the error will be returned. If cancellable is
cancelled, Gio.IOErrorEnum.CANCELLED is returned as with any other error.
an array of Gio.OutputMessage structs
an int containing Gio.SocketMsgFlags flags
the maximum time (in microseconds) to wait, 0 to not block, or -1 to block indefinitely
Optionalcancellable: Gio.Cancellablea %GCancellable
number of messages sent, or -1 on error. Note that the number of messages sent may be smaller than num_messages if timeout is zero or positive, or if num_messages was larger than UIO_MAXIOV (1024), in which case the caller may re-try to send the remaining messages.
Creates a binding between source_property on source and target_property
on target.
Whenever the source_property is changed the target_property is
updated using the same value. For instance:
g_object_bind_property (action, "active", widget, "sensitive", 0);
Will result in the "sensitive" property of the widget GObject.Object instance to be updated with the same value of the "active" property of the action GObject.Object instance.
If flags contains GObject.BindingFlags.BIDIRECTIONAL then the binding will be mutual:
if target_property on target changes then the source_property on source
will be updated as well.
The binding will automatically be removed when either the source or the
target instances are finalized. To remove the binding without affecting the
source and the target you can just call g_object_unref() on the returned
GObject.Binding instance.
Removing the binding by calling g_object_unref() on it must only be done if
the binding, source and target are only used from a single thread and it
is clear that both source and target outlive the binding. Especially it
is not safe to rely on this if the binding, source or target can be
finalized from different threads. Keep another reference to the binding and
use g_binding_unbind() instead to be on the safe side.
A GObject.Object can have multiple bindings.
the property on source to bind
the target GObject.Object
the property on target to bind
flags to pass to GObject.Binding
the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.
Complete version of g_object_bind_property().
Creates a binding between source_property on source and target_property
on target, allowing you to set the transformation functions to be used by
the binding.
If flags contains GObject.BindingFlags.BIDIRECTIONAL then the binding will be mutual:
if target_property on target changes then the source_property on source
will be updated as well. The transform_from function is only used in case
of bidirectional bindings, otherwise it will be ignored
The binding will automatically be removed when either the source or the
target instances are finalized. This will release the reference that is
being held on the GObject.Binding instance; if you want to hold on to the
GObject.Binding instance, you will need to hold a reference to it.
To remove the binding, call g_binding_unbind().
A GObject.Object can have multiple bindings.
The same user_data parameter will be used for both transform_to
and transform_from transformation functions; the notify function will
be called once, when the binding is removed. If you need different data
for each transformation function, please use
g_object_bind_property_with_closures() instead.
the property on source to bind
the target GObject.Object
the property on target to bind
flags to pass to GObject.Binding
Optionaltransform_to: BindingTransformFuncthe transformation function from the source to the target, or null to use the default
Optionaltransform_from: BindingTransformFuncthe transformation function from the target to the source, or null to use the default
Optionalnotify: DestroyNotifya function to call when disposing the binding, to free resources used by the transformation functions, or null if not required
the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.
Creates a binding between source_property on source and target_property
on target, allowing you to set the transformation functions to be used by
the binding.
This function is the language bindings friendly version of
g_object_bind_property_full(), using GClosures instead of
function pointers.
the property on source to bind
the target GObject.Object
the property on target to bind
flags to pass to GObject.Binding
a GObject.Closure wrapping the transformation function from the source to the target, or null to use the default
a GObject.Closure wrapping the transformation function from the target to the source, or null to use the default
the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.
Blocks a handler of an instance so it will not be called during any signal emissions
Handler ID of the handler to be blocked
SignalconnectSignalconnect_Disconnects a handler from an instance so it will not be called during any future or currently ongoing emissions of the signal it has been connected to.
Handler ID of the handler to be disconnected
SignalemitThis function is intended for GObject.Object implementations to re-enforce
a [floating][floating-ref] object reference. Doing this is seldom
required: all GInitiallyUnowneds are created with a floating reference
which usually just needs to be sunken by calling g_object_ref_sink().
Increases the freeze count on object. If the freeze count is
non-zero, the emission of "notify" signals on object is
stopped. The signals are queued until the freeze count is decreased
to zero. Duplicate notifications are squashed so that at most one
GObject.Object::notify signal is emitted for each property modified while the
object is frozen.
This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.
Gets a named field from the objects table of associations (see g_object_set_data()).
name of the key for that association
the data if found, or null if no such data exists.
Gets a property of an object.
The value can be:
In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling GObject.Value.unset.
Note that GObject.Object.get_property is really intended for language bindings, GObject.Object.get is much more convenient for C programming.
The name of the property to get
Return location for the property value. Can be an empty GObject.Value initialized by G_VALUE_INIT (auto-initialized with expected type since GLib 2.60), a GObject.Value initialized with the expected property type, or a GObject.Value initialized with a transformable type
This function gets back user data pointers stored via
g_object_set_qdata().
A GLib.Quark, naming the user data pointer
The user data pointer set, or null
Gets n_properties properties for an object.
Obtained properties will be set to values. All properties must be valid.
Warnings will be emitted and undefined behaviour may result if invalid
properties are passed in.
the names of each property to get
the values of each property to get
Checks whether object has a [floating][floating-ref] reference.
true if object has a floating reference
Emits a "notify" signal for the property property_name on object.
When possible, eg. when signaling a property change from within the class
that registered the property, you should use g_object_notify_by_pspec()
instead.
Note that emission of the notify signal may be blocked with
g_object_freeze_notify(). In this case, the signal emissions are queued
and will be emitted (in reverse order) when g_object_thaw_notify() is
called.
the name of a property installed on the class of object.
Emits a "notify" signal for the property specified by pspec on object.
This function omits the property name lookup, hence it is faster than
g_object_notify().
One way to avoid using g_object_notify() from within the
class that registered the properties, and using g_object_notify_by_pspec()
instead, is to store the GParamSpec used with
g_object_class_install_property() inside a static array, e.g.:
typedef enum
{
PROP_FOO = 1,
PROP_LAST
} MyObjectProperty;
static GParamSpec *properties[PROP_LAST];
static void
my_object_class_init (MyObjectClass *klass)
{
properties[PROP_FOO] = g_param_spec_int ("foo", NULL, NULL,
0, 100,
50,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
g_object_class_install_property (gobject_class,
PROP_FOO,
properties[PROP_FOO]);
}
and then notify a change on the "foo" property with:
g_object_notify_by_pspec (self, properties[PROP_FOO]);
the GObject.ParamSpec of a property installed on the class of object.
Increases the reference count of object.
Since GLib 2.56, if GLIB_VERSION_MAX_ALLOWED is 2.56 or greater, the type
of object will be propagated to the return type (using the GCC typeof()
extension), so any casting the caller needs to do on the return type must be
explicit.
the same object
Increase the reference count of object, and possibly remove the
[floating][floating-ref] reference, if object has a floating reference.
In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.
Since GLib 2.56, the type of object will be propagated to the return type
under the same conditions as for g_object_ref().
object
Releases all references to other objects. This can be used to break reference cycles.
This function should only be called from object system implementations.
Sets multiple properties of an object at once. The properties argument should be a dictionary mapping property names to values.
Object containing the properties to set
Each object carries around a table of associations from strings to pointers. This function lets you set an association.
If the object already had an association with that name, the old association will be destroyed.
Internally, the key is converted to a GLib.Quark using g_quark_from_string().
This means a copy of key is kept permanently (even after object has been
finalized) — so it is recommended to only use a small, bounded set of values
for key in your program, to avoid the GLib.Quark storage growing unbounded.
name of the key
Optionaldata: anydata to associate with that key
Sets a property on an object.
The name of the property to set
The value to set the property to
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
name of the key
the data if found, or null if no such data exists.
This function gets back user data pointers stored via
g_object_set_qdata() and removes the data from object
without invoking its destroy() function (if any was
set).
Usually, calling this function is only required to update
user data pointers with a destroy notifier, for example:
void
object_add_to_user_list (GObject *object,
const gchar *new_string)
{
// the quark, naming the object data
GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
// retrieve the old string list
GList *list = g_object_steal_qdata (object, quark_string_list);
// prepend new string
list = g_list_prepend (list, g_strdup (new_string));
// this changed 'list', so we need to set it again
g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
}
static void
free_string_list (gpointer data)
{
GList *node, *list = data;
for (node = list; node; node = node->next)
g_free (node->data);
g_list_free (list);
}
Using g_object_get_qdata() in the above example, instead of
g_object_steal_qdata() would have left the destroy function set,
and thus the partial string list would have been freed upon
g_object_set_qdata_full().
A GLib.Quark, naming the user data pointer
The user data pointer set, or null
Stops a signal's emission by the given signal name. This will prevent the default handler and any subsequent signal handlers from being invoked.
Name of the signal to stop emission of
Reverts the effect of a previous call to
g_object_freeze_notify(). The freeze count is decreased on object
and when it reaches zero, queued "notify" signals are emitted.
Duplicate notifications for each property are squashed so that at most one GObject.Object::notify signal is emitted for each property, in the reverse order in which they have been queued.
It is an error to call this function when the freeze count is zero.
Unblocks a handler so it will be called again during any signal emissions
Handler ID of the handler to be unblocked
Decreases the reference count of object. When its reference count
drops to 0, the object is finalized (i.e. its memory is freed).
If the pointer to the GObject.Object may be reused in future (for example, if it is
an instance variable of another object), it is recommended to clear the
pointer to null rather than retain a dangling pointer to a potentially
invalid GObject.Object instance. Use g_clear_object() for this.
Virtualvfunc_the constructed function is called by g_object_new() as the
final step of the object creation process. At the point of the call, all
construction properties have been set on the object. The purpose of this
call is to allow for object initialisation steps that can only be performed
after construction properties have been set. constructed implementors
should chain up to the constructed call of their parent class to allow it
to complete its initialisation.
Virtualvfunc_Virtualvfunc_the dispose function is supposed to drop all references to other
objects, but keep the instance otherwise intact, so that client method
invocations still work. It may be run multiple times (due to reference
loops). Before returning, dispose should chain up to the dispose method
of the parent class.
Virtualvfunc_instance finalization function, should finish the finalization of
the instance begun in dispose and chain up to the finalize method of the
parent class.
Virtualvfunc_Virtualvfunc_Emits a "notify" signal for the property property_name on object.
When possible, eg. when signaling a property change from within the class
that registered the property, you should use g_object_notify_by_pspec()
instead.
Note that emission of the notify signal may be blocked with
g_object_freeze_notify(). In this case, the signal emissions are queued
and will be emitted (in reverse order) when g_object_thaw_notify() is
called.
Virtualvfunc_the generic setter for all properties of this type. Should be
overridden for every type with properties. If implementations of
set_property don't emit property change notification explicitly, this will
be done implicitly by the type system. However, if the notify signal is
emitted explicitly, the type system will not emit it a second time.
This function essentially limits the life time of the closure to
the life time of the object. That is, when the object is finalized,
the closure is invalidated by calling g_closure_invalidate() on
it, in order to prevent invocations of the closure with a finalized
(nonexisting) object. Also, g_object_ref() and g_object_unref() are
added as marshal guards to the closure, to ensure that an extra
reference count is held on object during invocation of the
closure. Usually, this function will be called on closures that
use this object as closure data.
GObject.Closure to watch
Virtualvfunc_Checks on the readiness of datagram_based to perform operations. The
operations specified in condition are checked for and masked against the
currently-satisfied conditions on datagram_based. The result is returned.
GObject.IOCondition.IN will be set in the return value if data is available to read with
g_datagram_based_receive_messages(), or if the connection is closed remotely
(EOS); and if the datagram_based has not been closed locally using some
implementation-specific method (such as g_socket_close() or
g_socket_shutdown() with shutdown_read set, if it’s a Gio.Socket).
If the connection is shut down or closed (by calling g_socket_close() or
g_socket_shutdown() with shutdown_read set, if it’s a Gio.Socket, for
example), all calls to this function will return Gio.IOErrorEnum.CLOSED.
GObject.IOCondition.OUT will be set if it is expected that at least one byte can be sent
using g_datagram_based_send_messages() without blocking. It will not be set
if the datagram_based has been closed locally.
GObject.IOCondition.HUP will be set if the connection has been closed locally.
GObject.IOCondition.ERR will be set if there was an asynchronous error in transmitting data
previously enqueued using g_datagram_based_send_messages().
Note that on Windows, it is possible for an operation to return
Gio.IOErrorEnum.WOULD_BLOCK even immediately after
g_datagram_based_condition_check() has claimed that the Gio.DatagramBased is
ready for writing. Rather than calling g_datagram_based_condition_check() and
then writing to the Gio.DatagramBased if it succeeds, it is generally better to
simply try writing right away, and try again later if the initial attempt
returns Gio.IOErrorEnum.WOULD_BLOCK.
It is meaningless to specify GObject.IOCondition.ERR or GObject.IOCondition.HUP in condition; these
conditions will always be set in the output if they are true. Apart from
these flags, the output is guaranteed to be masked by condition.
This call never blocks.
a GObject.IOCondition mask to check
Virtualvfunc_Waits for up to timeout microseconds for condition to become true on
datagram_based. If the condition is met, true is returned.
If cancellable is cancelled before the condition is met, or if timeout is
reached before the condition is met, then false is returned and error is
set appropriately (Gio.IOErrorEnum.CANCELLED or Gio.IOErrorEnum.TIMED_OUT).
a GObject.IOCondition mask to wait for
the maximum time (in microseconds) to wait, 0 to not block, or -1 to block indefinitely
Optionalcancellable: Gio.CancellableVirtualvfunc_Creates a GLib.Source that can be attached to a GLib.MainContext to monitor for
the availability of the specified condition on the Gio.DatagramBased. The
GLib.Source keeps a reference to the datagram_based.
The callback on the source is of the Gio.DatagramBasedSourceFunc type.
It is meaningless to specify GObject.IOCondition.ERR or GObject.IOCondition.HUP in condition; these
conditions will always be reported in the callback if they are true.
If non-null, cancellable can be used to cancel the source, which will
cause the source to trigger, reporting the current condition (which is
likely 0 unless cancellation happened at the same time as a condition
change). You can check for this in the callback using
g_cancellable_is_cancelled().
a GObject.IOCondition mask to monitor
Optionalcancellable: Gio.CancellableVirtualvfunc_Receive one or more data messages from datagram_based in one go.
messages must point to an array of Gio.InputMessage structs and
num_messages must be the length of this array. Each Gio.InputMessage
contains a pointer to an array of Gio.InputVector structs describing the
buffers that the data received in each message will be written to.
flags modify how all messages are received. The commonly available
arguments for this are available in the Gio.SocketMsgFlags enum, but the
values there are the same as the system values, and the flags
are passed in as-is, so you can pass in system-specific flags too. These
flags affect the overall receive operation. Flags affecting individual
messages are returned in Gio.InputMessage.flags.
The other members of Gio.InputMessage are treated as described in its documentation.
If timeout is negative the call will block until num_messages have been
received, the connection is closed remotely (EOS), cancellable is cancelled,
or an error occurs.
If timeout is 0 the call will return up to num_messages without blocking,
or Gio.IOErrorEnum.WOULD_BLOCK if no messages are queued in the operating system
to be received.
If timeout is positive the call will block on the same conditions as if
timeout were negative. If the timeout is reached
before any messages are received, Gio.IOErrorEnum.TIMED_OUT is returned,
otherwise it will return the number of messages received before timing out.
(Note: This is effectively the behaviour of MSG_WAITFORONE with
recvmmsg().)
To be notified when messages are available, wait for the GObject.IOCondition.IN condition.
Note though that you may still receive Gio.IOErrorEnum.WOULD_BLOCK from
g_datagram_based_receive_messages() even if you were previously notified of a
GObject.IOCondition.IN condition.
If the remote peer closes the connection, any messages queued in the
underlying receive buffer will be returned, and subsequent calls to
g_datagram_based_receive_messages() will return 0 (with no error set).
If the connection is shut down or closed (by calling g_socket_close() or
g_socket_shutdown() with shutdown_read set, if it’s a Gio.Socket, for
example), all calls to this function will return Gio.IOErrorEnum.CLOSED.
On error -1 is returned and error is set accordingly. An error will only
be returned if zero messages could be received; otherwise the number of
messages successfully received before the error will be returned. If
cancellable is cancelled, Gio.IOErrorEnum.CANCELLED is returned as with any
other error.
an array of Gio.InputMessage structs
an int containing Gio.SocketMsgFlags flags for the overall operation
the maximum time (in microseconds) to wait, 0 to not block, or -1 to block indefinitely
Optionalcancellable: Gio.Cancellablea %GCancellable
Virtualvfunc_Send one or more data messages from datagram_based in one go.
messages must point to an array of Gio.OutputMessage structs and
num_messages must be the length of this array. Each Gio.OutputMessage
contains an address to send the data to, and a pointer to an array of
Gio.OutputVector structs to describe the buffers that the data to be sent
for each message will be gathered from.
flags modify how the message is sent. The commonly available arguments
for this are available in the Gio.SocketMsgFlags enum, but the
values there are the same as the system values, and the flags
are passed in as-is, so you can pass in system-specific flags too.
The other members of Gio.OutputMessage are treated as described in its documentation.
If timeout is negative the call will block until num_messages have been
sent, cancellable is cancelled, or an error occurs.
If timeout is 0 the call will send up to num_messages without blocking,
or will return Gio.IOErrorEnum.WOULD_BLOCK if there is no space to send messages.
If timeout is positive the call will block on the same conditions as if
timeout were negative. If the timeout is reached before any messages are
sent, Gio.IOErrorEnum.TIMED_OUT is returned, otherwise it will return the number
of messages sent before timing out.
To be notified when messages can be sent, wait for the GObject.IOCondition.OUT condition.
Note though that you may still receive Gio.IOErrorEnum.WOULD_BLOCK from
g_datagram_based_send_messages() even if you were previously notified of a
GObject.IOCondition.OUT condition. (On Windows in particular, this is very common due to
the way the underlying APIs work.)
If the connection is shut down or closed (by calling g_socket_close() or
g_socket_shutdown() with shutdown_write set, if it’s a Gio.Socket, for
example), all calls to this function will return Gio.IOErrorEnum.CLOSED.
On error -1 is returned and error is set accordingly. An error will only
be returned if zero messages could be sent; otherwise the number of messages
successfully sent before the error will be returned. If cancellable is
cancelled, Gio.IOErrorEnum.CANCELLED is returned as with any other error.
an array of Gio.OutputMessage structs
an int containing Gio.SocketMsgFlags flags
the maximum time (in microseconds) to wait, 0 to not block, or -1 to block indefinitely
Optionalcancellable: Gio.Cancellablea %GCancellable
Interface for socket-like objects with datagram semantics.
A Gio.DatagramBased is a networking interface for representing datagram-based communications. It is a more or less direct mapping of the core parts of the BSD socket API in a portable GObject interface. It is implemented by Gio.Socket, which wraps the UNIX socket API on UNIX and winsock2 on Windows.
Gio.DatagramBased is entirely platform independent, and is intended to be used alongside higher-level networking APIs such as Gio.IOStream.
It uses vectored scatter/gather I/O by default, allowing for many messages to be sent or received in a single call. Where possible, implementations of the interface should take advantage of vectored I/O to minimise processing or system calls. For example, Gio.Socket uses
recvmmsg()andsendmmsg()where possible. Callers should take advantage of scatter/gather I/O (the use of multiple buffers per message) to avoid unnecessary copying of data to assemble or disassemble a message.Each Gio.DatagramBased operation has a timeout parameter which may be negative for blocking behaviour, zero for non-blocking behaviour, or positive for timeout behaviour. A blocking operation blocks until finished or there is an error. A non-blocking operation will return immediately with a
G_IO_ERROR_WOULD_BLOCKerror if it cannot make progress. A timeout operation will block until the operation is complete or the timeout expires; if the timeout expires it will return what progress it made, orG_IO_ERROR_TIMED_OUTif no progress was made. To know when a call would successfully run you can call Gio.DatagramBased.condition_check or Gio.DatagramBased.condition_wait. You can also use Gio.DatagramBased.create_source and attach it to a GLib.MainContext to get callbacks when I/O is possible.When running a non-blocking operation applications should always be able to handle getting a
G_IO_ERROR_WOULD_BLOCKerror even when some other function said that I/O was possible. This can easily happen in case of a race condition in the application, but it can also happen for other reasons. For instance, on Windows a socket is always seen as writable until a write returnsG_IO_ERROR_WOULD_BLOCK.As with Gio.Socket, Gio.DatagramBaseds can be either connection oriented (for example, SCTP) or connectionless (for example, UDP). Gio.DatagramBaseds must be datagram-based, not stream-based. The interface does not cover connection establishment — use methods on the underlying type to establish a connection before sending and receiving data through the Gio.DatagramBased API. For connectionless socket types the target/source address is specified or received in each I/O operation.
Like most other APIs in GLib, Gio.DatagramBased is not inherently thread safe. To use a Gio.DatagramBased concurrently from multiple threads, you must implement your own locking.
Since
2.48