sf_data_in Your function for handling incoming data. May be null. Declarationsf_data_in_func sf_data_in; See AlsoFieldssf_handlesf_flagssf_namesf_unregisteredsf_attachsf_detachsf_notifysf_data_outsf_connect_insf_connect_outsf_bindsf_setoptionsf_getoptionsf_listensf_ioctlsf_lensf_ext_acceptsf_ext_rsvd