Claim ownership of a given selection for a particular widget, or, if @widget is %NULL, release ownership of the selection.
the #GdkDisplay where the selection is set
new selection owner (a #GtkWidget), or %NULL.
an interned atom representing the selection to claim.
timestamp with which to claim the selection
Return: TRUE if the operation succeeded
2.2
See Implementation
Claim ownership of a given selection for a particular widget, or, if @widget is %NULL, release ownership of the selection.