Note that this is a “shallow” copy. If the list elements
consist of pointers to data, the pointers are copied but
the actual data is not. See
g_list_copy_deep() if you need
to copy the data as well.
This function is not directly available to language bindings.
Type: A list of
GList, this must point to the top of the list.
The data is owned by the caller of the function.