Closures

Closures — Functions as first-class objects

Synopsis

#include <glib-object.h>

#define             G_CLOSURE_NEEDS_MARSHAL             (closure)
#define             G_CLOSURE_N_NOTIFIERS               (cl)
#define             G_CCLOSURE_SWAP_DATA                (cclosure)
#define             G_CALLBACK                          (f)
void                (*GCallback)                        (void);
struct              GClosure;
#define             G_TYPE_CLOSURE
struct              GCClosure;
void                (*GClosureMarshal)                  (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                (*GClosureNotify)                   (gpointer data,
                                                         GClosure *closure);
GClosure *          g_cclosure_new                      (GCallback callback_func,
                                                         gpointer user_data,
                                                         GClosureNotify destroy_data);
GClosure *          g_cclosure_new_swap                 (GCallback callback_func,
                                                         gpointer user_data,
                                                         GClosureNotify destroy_data);
GClosure *          g_cclosure_new_object               (GCallback callback_func,
                                                         GObject *object);
GClosure *          g_cclosure_new_object_swap          (GCallback callback_func,
                                                         GObject *object);
GClosure *          g_closure_new_object                (guint sizeof_closure,
                                                         GObject *object);
GClosure *          g_closure_ref                       (GClosure *closure);
void                g_closure_sink                      (GClosure *closure);
void                g_closure_unref                     (GClosure *closure);
void                g_closure_invoke                    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint);
void                g_closure_invalidate                (GClosure *closure);
void                g_closure_add_finalize_notifier     (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);
void                g_closure_add_invalidate_notifier   (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);
void                g_closure_remove_finalize_notifier  (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);
void                g_closure_remove_invalidate_notifier
                                                        (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);
GClosure *          g_closure_new_simple                (guint sizeof_closure,
                                                         gpointer data);
void                g_closure_set_marshal               (GClosure *closure,
                                                         GClosureMarshal marshal);
void                g_closure_add_marshal_guards        (GClosure *closure,
                                                         gpointer pre_marshal_data,
                                                         GClosureNotify pre_marshal_notify,
                                                         gpointer post_marshal_data,
                                                         GClosureNotify post_marshal_notify);
void                g_closure_set_meta_marshal          (GClosure *closure,
                                                         gpointer marshal_data,
                                                         GClosureMarshal meta_marshal);
void                g_source_set_closure                (GSource *source,
                                                         GClosure *closure);
void                g_source_set_dummy_callback         (GSource *source);
#define             G_TYPE_IO_CHANNEL
#define             G_TYPE_IO_CONDITION

void                g_cclosure_marshal_VOID__VOID       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__BOOLEAN    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__CHAR       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__UCHAR      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__INT        (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__UINT       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__LONG       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__ULONG      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__ENUM       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__FLAGS      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__FLOAT      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__DOUBLE     (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__STRING     (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__PARAM      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__BOXED      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__POINTER    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__OBJECT     (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__VARIANT    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_STRING__OBJECT_POINTER
                                                        (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_VOID__UINT_POINTER
                                                        (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
void                g_cclosure_marshal_BOOLEAN__FLAGS   (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);
#define             g_cclosure_marshal_BOOL__FLAGS

Description

A GClosure represents a callback supplied by the programmer. It will generally comprise a function of some kind and a marshaller used to call it. It is the reponsibility of the marshaller to convert the arguments for the invocation from GValues into a suitable form, perform the callback on the converted arguments, and transform the return value back into a GValue.

In the case of C programs, a closure usually just holds a pointer to a function and maybe a data argument, and the marshaller converts between GValue and native C types. The GObject library provides the GCClosure type for this purpose. Bindings for other languages need marshallers which convert between GValues and suitable representations in the runtime of the language in order to use functions written in that languages as callbacks.

Within GObject, closures play an important role in the implementation of signals. When a signal is registered, the c_marshaller argument to g_signal_new() specifies the default C marshaller for any closure which is connected to this signal. GObject provides a number of C marshallers for this purpose, see the g_cclosure_marshal_*() functions. Additional C marshallers can be generated with the glib-genmarshal utility. Closures can be explicitly connected to signals with g_signal_connect_closure(), but it usually more convenient to let GObject create a closure automatically by using one of the g_signal_connect_*() functions which take a callback function/user data pair.

Using closures has a number of important advantages over a simple callback function/data pointer combination:

  • Closures allow the callee to get the types of the callback parameters, which means that language bindings don't have to write individual glue for each callback type.

  • The reference counting of GClosure makes it easy to handle reentrancy right; if a callback is removed while it is being invoked, the closure and its parameters won't be freed until the invocation finishes.

  • g_closure_invalidate() and invalidation notifiers allow callbacks to be automatically removed when the objects they point to go away.

Details

G_CLOSURE_NEEDS_MARSHAL()

#define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)

Check if the closure still needs a marshaller. See g_closure_set_marshal().

closure :

a GClosure

Returns :

TRUE if a GClosureMarshal marshaller has not yet been set on closure.

G_CLOSURE_N_NOTIFIERS()

#define             G_CLOSURE_N_NOTIFIERS(cl)

Get the total number of notifiers connected with the closure cl. The count includes the meta marshaller, the finalize and invalidate notifiers and the marshal guards. Note that each guard counts as two notifiers. See g_closure_set_meta_marshal(), g_closure_add_finalize_notifier(), g_closure_add_invalidate_notifier() and g_closure_add_marshal_guards().

cl :

a GClosure

Returns :

number of notifiers

G_CCLOSURE_SWAP_DATA()

#define G_CCLOSURE_SWAP_DATA(cclosure)	 (((GClosure*) (cclosure))->derivative_flag)

Checks whether the user data of the GCClosure should be passed as the first parameter to the callback. See g_cclosure_new_swap().

cclosure :

a GCClosure

Returns :

TRUE if data has to be swapped.

G_CALLBACK()

#define G_CALLBACK(f)			 ((GCallback) (f))

Cast a function pointer to a GCallback.

f :

a function pointer.

GCallback ()

void                (*GCallback)                        (void);

The type used for callback functions in structure definitions and function signatures. This doesn't mean that all callback functions must take no parameters and return void. The required signature of a callback function is determined by the context in which is used (e.g. the signal to which it is connected). Use G_CALLBACK() to cast the callback function to a GCallback.


struct GClosure

struct GClosure {
  volatile       	guint	 in_marshal : 1;
  volatile       	guint	 is_invalid : 1;
};

A GClosure represents a callback supplied by the programmer.

volatile        guint in_marshal : 1;

Indicates whether the closure is currently being invoked with g_closure_invoke()

volatile        guint is_invalid : 1;

Indicates whether the closure has been invalidated by g_closure_invalidate()

G_TYPE_CLOSURE

#define G_TYPE_CLOSURE		(g_closure_get_type ())

The GType for GClosure.


struct GCClosure

struct GCClosure {
  GClosure closure;
  gpointer callback;
};

A GCClosure is a specialization of GClosure for C function callbacks.

GClosure closure;

the GClosure

gpointer callback;

the callback function

GClosureMarshal ()

void                (*GClosureMarshal)                  (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

The type used for marshaller functions.

closure :

the GClosure to which the marshaller belongs

return_value :

a GValue to store the return value. May be NULL if the callback of closure doesn't return a value.

n_param_values :

the length of the param_values array

param_values :

an array of GValues holding the arguments on which to invoke the callback of closure

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller, see g_closure_set_marshal() and g_closure_set_meta_marshal()

GClosureNotify ()

void                (*GClosureNotify)                   (gpointer data,
                                                         GClosure *closure);

The type used for the various notification callbacks which can be registered on closures.

data :

data specified when registering the notification callback

closure :

the GClosure on which the notification is emitted

g_cclosure_new ()

GClosure *          g_cclosure_new                      (GCallback callback_func,
                                                         gpointer user_data,
                                                         GClosureNotify destroy_data);

Creates a new closure which invokes callback_func with user_data as the last parameter.

callback_func :

the function to invoke

user_data :

user data to pass to callback_func

destroy_data :

destroy notify to be called when user_data is no longer used

Returns :

a new GCClosure

g_cclosure_new_swap ()

GClosure *          g_cclosure_new_swap                 (GCallback callback_func,
                                                         gpointer user_data,
                                                         GClosureNotify destroy_data);

Creates a new closure which invokes callback_func with user_data as the first parameter.

callback_func :

the function to invoke

user_data :

user data to pass to callback_func

destroy_data :

destroy notify to be called when user_data is no longer used

Returns :

a new GCClosure. [transfer full]

g_cclosure_new_object ()

GClosure *          g_cclosure_new_object               (GCallback callback_func,
                                                         GObject *object);

A variant of g_cclosure_new() which uses object as user_data and calls g_object_watch_closure() on object and the created closure. This function is useful when you have a callback closely associated with a GObject, and want the callback to no longer run after the object is is freed.

callback_func :

the function to invoke

object :

a GObject pointer to pass to callback_func

Returns :

a new GCClosure

g_cclosure_new_object_swap ()

GClosure *          g_cclosure_new_object_swap          (GCallback callback_func,
                                                         GObject *object);

A variant of g_cclosure_new_swap() which uses object as user_data and calls g_object_watch_closure() on object and the created closure. This function is useful when you have a callback closely associated with a GObject, and want the callback to no longer run after the object is is freed.

callback_func :

the function to invoke

object :

a GObject pointer to pass to callback_func

Returns :

a new GCClosure

g_closure_new_object ()

GClosure *          g_closure_new_object                (guint sizeof_closure,
                                                         GObject *object);

A variant of g_closure_new_simple() which stores object in the data field of the closure and calls g_object_watch_closure() on object and the created closure. This function is mainly useful when implementing new types of closures.

sizeof_closure :

the size of the structure to allocate, must be at least sizeof (GClosure)

object :

a GObject pointer to store in the data field of the newly allocated GClosure

Returns :

a newly allocated GClosure. [transfer full]

g_closure_ref ()

GClosure *          g_closure_ref                       (GClosure *closure);

Increments the reference count on a closure to force it staying alive while the caller holds a pointer to it.

closure :

GClosure to increment the reference count on

Returns :

The closure passed in, for convenience. [transfer none]

g_closure_sink ()

void                g_closure_sink                      (GClosure *closure);

Takes over the initial ownership of a closure. Each closure is initially created in a floating state, which means that the initial reference count is not owned by any caller. g_closure_sink() checks to see if the object is still floating, and if so, unsets the floating state and decreases the reference count. If the closure is not floating, g_closure_sink() does nothing. The reason for the existance of the floating state is to prevent cumbersome code sequences like:

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closure = g_cclosure_new (cb_func, cb_data);
g_source_set_closure (source, closure);
g_closure_unref (closure); // XXX GObject doesn't really need this

Because g_source_set_closure() (and similar functions) take ownership of the initial reference count, if it is unowned, we instead can write:

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g_source_set_closure (source, g_cclosure_new (cb_func, cb_data));

Generally, this function is used together with g_closure_ref(). Ane example of storing a closure for later notification looks like:

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static GClosure *notify_closure = NULL;
void
foo_notify_set_closure (GClosure *closure)
{
  if (notify_closure)
    g_closure_unref (notify_closure);
  notify_closure = closure;
  if (notify_closure)
    {
      g_closure_ref (notify_closure);
      g_closure_sink (notify_closure);
    }
}

Because g_closure_sink() may decrement the reference count of a closure (if it hasn't been called on closure yet) just like g_closure_unref(), g_closure_ref() should be called prior to this function.

closure :

GClosure to decrement the initial reference count on, if it's still being held

g_closure_unref ()

void                g_closure_unref                     (GClosure *closure);

Decrements the reference count of a closure after it was previously incremented by the same caller. If no other callers are using the closure, then the closure will be destroyed and freed.

closure :

GClosure to decrement the reference count on

g_closure_invoke ()

void                g_closure_invoke                    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint);

Invokes the closure, i.e. executes the callback represented by the closure.

closure :

a GClosure

return_value :

a GValue to store the return value. May be NULL if the callback of closure doesn't return a value.

n_param_values :

the length of the param_values array

param_values :

an array of GValues holding the arguments on which to invoke the callback of closure. [array length=n_param_values]

invocation_hint :

a context-dependent invocation hint

g_closure_invalidate ()

void                g_closure_invalidate                (GClosure *closure);

Sets a flag on the closure to indicate that its calling environment has become invalid, and thus causes any future invocations of g_closure_invoke() on this closure to be ignored. Also, invalidation notifiers installed on the closure will be called at this point. Note that unless you are holding a reference to the closure yourself, the invalidation notifiers may unref the closure and cause it to be destroyed, so if you need to access the closure after calling g_closure_invalidate(), make sure that you've previously called g_closure_ref().

Note that g_closure_invalidate() will also be called when the reference count of a closure drops to zero (unless it has already been invalidated before).

closure :

GClosure to invalidate

g_closure_add_finalize_notifier ()

void                g_closure_add_finalize_notifier     (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);

Registers a finalization notifier which will be called when the reference count of closure goes down to 0. Multiple finalization notifiers on a single closure are invoked in unspecified order. If a single call to g_closure_unref() results in the closure being both invalidated and finalized, then the invalidate notifiers will be run before the finalize notifiers.

closure :

a GClosure

notify_data :

data to pass to notify_func

notify_func :

the callback function to register

g_closure_add_invalidate_notifier ()

void                g_closure_add_invalidate_notifier   (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);

Registers an invalidation notifier which will be called when the closure is invalidated with g_closure_invalidate(). Invalidation notifiers are invoked before finalization notifiers, in an unspecified order.

closure :

a GClosure

notify_data :

data to pass to notify_func

notify_func :

the callback function to register

g_closure_remove_finalize_notifier ()

void                g_closure_remove_finalize_notifier  (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);

Removes a finalization notifier.

Notice that notifiers are automatically removed after they are run.

closure :

a GClosure

notify_data :

data which was passed to g_closure_add_finalize_notifier() when registering notify_func

notify_func :

the callback function to remove

g_closure_remove_invalidate_notifier ()

void                g_closure_remove_invalidate_notifier
                                                        (GClosure *closure,
                                                         gpointer notify_data,
                                                         GClosureNotify notify_func);

Removes an invalidation notifier.

Notice that notifiers are automatically removed after they are run.

closure :

a GClosure

notify_data :

data which was passed to g_closure_add_invalidate_notifier() when registering notify_func

notify_func :

the callback function to remove

g_closure_new_simple ()

GClosure *          g_closure_new_simple                (guint sizeof_closure,
                                                         gpointer data);

Allocates a struct of the given size and initializes the initial part as a GClosure. This function is mainly useful when implementing new types of closures.

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typedef struct _MyClosure MyClosure;
struct _MyClosure
{
  GClosure closure;
  // extra data goes here
};

static void
my_closure_finalize (gpointer  notify_data,
                     GClosure *closure)
{
  MyClosure *my_closure = (MyClosure *)closure;

  // free extra data here
}

MyClosure *my_closure_new (gpointer data)
{
  GClosure *closure;
  MyClosure *my_closure;

  closure = g_closure_new_simple (sizeof (MyClosure), data);
  my_closure = (MyClosure *) closure;

  // initialize extra data here

  g_closure_add_finalize_notifier (closure, notify_data,
                                   my_closure_finalize);
  return my_closure;
}

sizeof_closure :

the size of the structure to allocate, must be at least sizeof (GClosure)

data :

data to store in the data field of the newly allocated GClosure

Returns :

a newly allocated GClosure. [transfer full]

g_closure_set_marshal ()

void                g_closure_set_marshal               (GClosure *closure,
                                                         GClosureMarshal marshal);

Sets the marshaller of closure. The marshal_data of marshal provides a way for a meta marshaller to provide additional information to the marshaller. (See g_closure_set_meta_marshal().) For GObject's C predefined marshallers (the g_cclosure_marshal_*() functions), what it provides is a callback function to use instead of closure->callback.

closure :

a GClosure

marshal :

a GClosureMarshal function

g_closure_add_marshal_guards ()

void                g_closure_add_marshal_guards        (GClosure *closure,
                                                         gpointer pre_marshal_data,
                                                         GClosureNotify pre_marshal_notify,
                                                         gpointer post_marshal_data,
                                                         GClosureNotify post_marshal_notify);

Adds a pair of notifiers which get invoked before and after the closure callback, respectively. This is typically used to protect the extra arguments for the duration of the callback. See g_object_watch_closure() for an example of marshal guards.

closure :

a GClosure

pre_marshal_data :

data to pass to pre_marshal_notify

pre_marshal_notify :

a function to call before the closure callback

post_marshal_data :

data to pass to post_marshal_notify

post_marshal_notify :

a function to call after the closure callback

g_closure_set_meta_marshal ()

void                g_closure_set_meta_marshal          (GClosure *closure,
                                                         gpointer marshal_data,
                                                         GClosureMarshal meta_marshal);

Sets the meta marshaller of closure. A meta marshaller wraps closure->marshal and modifies the way it is called in some fashion. The most common use of this facility is for C callbacks. The same marshallers (generated by glib-genmarshal) are used everywhere, but the way that we get the callback function differs. In most cases we want to use closure->callback, but in other cases we want to use some different technique to retrieve the callback function.

For example, class closures for signals (see g_signal_type_cclosure_new()) retrieve the callback function from a fixed offset in the class structure. The meta marshaller retrieves the right callback and passes it to the marshaller as the marshal_data argument.

closure :

a GClosure

marshal_data :

context-dependent data to pass to meta_marshal

meta_marshal :

a GClosureMarshal function

g_source_set_closure ()

void                g_source_set_closure                (GSource *source,
                                                         GClosure *closure);

Set the callback for a source as a GClosure.

If the source is not one of the standard GLib types, the closure_callback and closure_marshal fields of the GSourceFuncs structure must have been filled in with pointers to appropriate functions.

source :

the source

closure :

a GClosure

g_source_set_dummy_callback ()

void                g_source_set_dummy_callback         (GSource *source);

Sets a dummy callback for source. The callback will do nothing, and if the source expects a gboolean return value, it will return TRUE. (If the source expects any other type of return value, it will return a 0/NULL value; whatever g_value_init() initializes a GValue to for that type.)

If the source is not one of the standard GLib types, the closure_callback and closure_marshal fields of the GSourceFuncs structure must have been filled in with pointers to appropriate functions.

source :

the source

G_TYPE_IO_CHANNEL

#define G_TYPE_IO_CHANNEL (g_io_channel_get_type ())

The GType for GIOChannel.


G_TYPE_IO_CONDITION

#define G_TYPE_IO_CONDITION (g_io_condition_get_type ())

The GType for GIOCondition.


g_cclosure_marshal_VOID__VOID ()

void                g_cclosure_marshal_VOID__VOID       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

1

param_values :

a GValue array holding only the instance

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__BOOLEAN ()

void                g_cclosure_marshal_VOID__BOOLEAN    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gboolean arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gboolean parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__CHAR ()

void                g_cclosure_marshal_VOID__CHAR       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gchar arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gchar parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__UCHAR ()

void                g_cclosure_marshal_VOID__UCHAR      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, guchar arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the guchar parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__INT ()

void                g_cclosure_marshal_VOID__INT        (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gint arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gint parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__UINT ()

void                g_cclosure_marshal_VOID__UINT       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, guint arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the guint parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__LONG ()

void                g_cclosure_marshal_VOID__LONG       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, glong arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the glong parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__ULONG ()

void                g_cclosure_marshal_VOID__ULONG      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gulong arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gulong parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__ENUM ()

void                g_cclosure_marshal_VOID__ENUM       (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gint arg1, gpointer user_data) where the gint parameter denotes an enumeration type..

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the enumeration parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__FLAGS ()

void                g_cclosure_marshal_VOID__FLAGS      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gint arg1, gpointer user_data) where the gint parameter denotes a flags type.

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the flags parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__FLOAT ()

void                g_cclosure_marshal_VOID__FLOAT      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gfloat arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gfloat parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__DOUBLE ()

void                g_cclosure_marshal_VOID__DOUBLE     (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gdouble arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gdouble parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__STRING ()

void                g_cclosure_marshal_VOID__STRING     (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, const gchar *arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gchar* parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__PARAM ()

void                g_cclosure_marshal_VOID__PARAM      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, GParamSpec *arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the GParamSpec* parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__BOXED ()

void                g_cclosure_marshal_VOID__BOXED      (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, GBoxed *arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the GBoxed* parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__POINTER ()

void                g_cclosure_marshal_VOID__POINTER    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, gpointer arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the gpointer parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__OBJECT ()

void                g_cclosure_marshal_VOID__OBJECT     (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, GObject *arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the GObject* parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__VARIANT ()

void                g_cclosure_marshal_VOID__VARIANT    (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, GVariant *arg1, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

2

param_values :

a GValue array holding the instance and the GVariant* parameter

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

Since 2.26


g_cclosure_marshal_STRING__OBJECT_POINTER ()

void                g_cclosure_marshal_STRING__OBJECT_POINTER
                                                        (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type gchar* (*callback) (gpointer instance, GObject *arg1, gpointer arg2, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

a GValue, which can store the returned string

n_param_values :

3

param_values :

a GValue array holding instance, arg1 and arg2

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_VOID__UINT_POINTER ()

void                g_cclosure_marshal_VOID__UINT_POINTER
                                                        (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type void (*callback) (gpointer instance, guint arg1, gpointer arg2, gpointer user_data).

closure :

the GClosure to which the marshaller belongs

return_value :

ignored

n_param_values :

3

param_values :

a GValue array holding instance, arg1 and arg2

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_BOOLEAN__FLAGS ()

void                g_cclosure_marshal_BOOLEAN__FLAGS   (GClosure *closure,
                                                         GValue *return_value,
                                                         guint n_param_values,
                                                         const GValue *param_values,
                                                         gpointer invocation_hint,
                                                         gpointer marshal_data);

A marshaller for a GCClosure with a callback of type gboolean (*callback) (gpointer instance, gint arg1, gpointer user_data) where the gint parameter denotes a flags type.

closure :

the GClosure to which the marshaller belongs

return_value :

a GValue which can store the returned gboolean

n_param_values :

2

param_values :

a GValue array holding instance and arg1

invocation_hint :

the invocation hint given as the last argument to g_closure_invoke()

marshal_data :

additional data specified when registering the marshaller

g_cclosure_marshal_BOOL__FLAGS

#define             g_cclosure_marshal_BOOL__FLAGS

Another name for g_cclosure_marshal_BOOLEAN__FLAGS().