c_gtk_tree_sortable_set_default_sort_func

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
void function(GtkTreeSortable* sortable, GtkTreeIterCompareFunc sortFunc, void* userData, GDestroyNotify destroy) c_gtk_tree_sortable_set_default_sort_func;

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