Five standard window routines accompany each panel. The first two trial_read_data() and trial_data_refresh() were mentioned above. A routine named trial_open() is used to create and open the panel. A routine named trial_field_manager() is used to handle the custom fields on the panel. And last, a routine named trial_init() is used to handle the data structure which accompanies the panel. These routines should be placed in a file named trial.c. We now discuss each of these routines in turn.