int set_field_init(FORM *form, Form_Hook func);
Form_Hook field_init(const FORM *form);
int set_field_term(FORM *form, Form_Hook func);
Form_Hook field_term(const FORM *form);
int set_form_init(FORM *form, Form_Hook func);
Form_Hook form_init(const FORM *form);
int set_form_term(FORM *form, Form_Hook func);
Form_Hook form_term(const FORM *form);
The function set_field_init sets a hook to be called at form-post time and each time the selected field changes (after the change). field_init returns the current field init hook, if any (NULL if there is no such hook).
The function set_field_term sets a hook to be called at form-unpost time and each time the selected field changes (before the change). field_term returns the current field term hook, if any (NULL if there is no such hook).
The function set_form_init sets a hook to be called at form-post time and just after a page change once it is posted. form_init returns the current form init hook, if any (NULL if there is no such hook).
The function set_form_term sets a hook to be called at form-unpost time and just before a page change once it is posted. form_init returns the current form term hook, if any (NULL if there is no such hook).