Retrieves the group assigned to a radio button.
Return: a linked list containing all the radio buttons in the same group as @radio_button. The returned list is owned by the radio button and must not be modified or freed.
See Implementation
Retrieves the group assigned to a radio button.
Return: a linked list containing all the radio buttons in the same group as @radio_button. The returned list is owned by the radio button and must not be modified or freed.