Selections
functions for transfering data via the X selection mechanism.
The X selection mechanism provides a way to transfer
arbitrary chunks of data between programs.
A selection is a essentially
a named clipboard, identified by a string interned
as a #GdkAtom. By claiming ownership of a selection,
an application indicates that it will be responsible
for supplying its contents. The most common
selections are PRIMARY and
CLIPBOARD.
The contents of a selection can be represented in
a number of formats, called targets.
Each target is identified by an atom. A list of
all possible targets supported by the selection owner
can be retrieved by requesting the special target
TARGETS. When a selection is
retrieved, the data is accompanied by a type
(an atom), and a format (an integer, representing
the number of bits per item).
See Properties and Atoms
for more information.
The functions in this section only contain the lowlevel
parts of the selection protocol. A considerably more
complicated implementation is needed on top of this.
GTK+ contains such an implementation in the functions
in gtkselection.h and programmers
should use those functions instead of the ones presented
here. If you plan to implement selection handling
directly on top of the functions here, you should refer
to the X Inter-client Communication Conventions Manual
(ICCCM).
The #GdkSelection enumeration contains predefined
atom values for several common selections.
The #GdkSelectionType enumeration contains predefined
atom values used to represent the types of data transferred
in response to a request for a target. See the
ICCCM for details about what data should be transferred
for each of these types. Other atoms can be used,
and the recommended practice for GTK+ is to to use mime
types for this purpose. However, supporting these types
may be useful for compatibility with older programs.
The #GdkTarget enumeration contains predefined atom values which are
used to describe possible targets for a selection. Other atoms can be
used, and the recommended practice for GTK+ is to to use mime types
for this purpose. However, supporting these types may be useful for
compatibility with older programs.
A #GdkAtom representing the PRIMARY selection.
A #GdkAtom representing the SECONDARY selection.
A #GdkAtom representing the CLIPBOARD selection.
A #GdkAtom representing the BITMAP selection target.
A #GdkAtom representing the COLORMAP selection target.
A #GdkAtom representing the DRAWABLE selection target.
A #GdkAtom representing the PIXMAP selection target.
A #GdkAtom representing the STRING selection target.
A #GdkAtom representing the ATOM selection type.
A #GdkAtom representing the BITMAP selection type.
A #GdkAtom representing the COLORMAP selection type.
A #GdkAtom representing the DRAWABLE selection type.
A #GdkAtom representing the INTEGER selection type.
A #GdkAtom representing the PIXMAP selection type.
A #GdkAtom representing the WINDOW selection type.
A #GdkAtom representing the STRING selection type.
Sets the owner of the given selection.
@owner: a #GdkWindow or %NULL to indicate that the
the owner for the given should be unset.
@selection: an atom identifying a selection.
@time: timestamp to use when setting the selection.
If this is older than the timestamp given last
time the owner was set for the given selection, the
request will be ignored.
@send_event: if %TRUE, and the new owner is different
from the current owner, the current owner
will be sent a SelectionClear event.
@Returns: %TRUE if the selection owner was successfully
changed to @owner, otherwise %FALSE.
Determines the owner of the given selection.
@selection: an atom indentifying a selection.
@Returns: if there is a selection owner for this window,
and it is a window known to the current process,
the #GdkWindow that owns the selection, otherwise
%NULL. Note that the return value may be owned
by a different process if a foreign window
was previously created for that window, but
a new foreign window will never be created by
this call.
Retrieves the contents of a selection in a given
form.
@requestor: a #GdkWindow.
@selection: an atom identifying the selection to get the
contents of.
@target: the form in which to retrieve the selection.
@time: the timestamp to use when retrieving the
selection. The selection owner may refuse the
request if it did not own the selection at
the time indicated by the timestamp.
Retrieves selection data that was stored by the selection
data in response to a call to gdk_selection_convert().
@requestor: the window on which the data is stored
@data: location to store a pointer to the retrieved data.
If the retrieval failed, %NULL we be stored here, otherwise, it
will be non-%NULL and the returned data should be freed with g_free()
when you are finished using it. The length of the
allocated memory is one more than the the length
of the returned data, and the final byte will always
be zero, to ensure nul-termination of strings.
@prop_type: location to store the type of the property.
@prop_format: location to store the format of the property.
@Returns: the length of the retrieved data.
Sends a response to SelectionRequest event.
@requestor: window to which to deliver response.
@selection: selection that was requested.
@target: target that was selected.
@property: property in which the selection owner stored the
data, or %GDK_NONE to indicate that the request
was rejected.
@time: timestamp.