SLIST_HEAD
SLIST_HEAD(, map_node) hscb_maps;
SLIST_HEAD(, map_node) sg_maps;
SLIST_HEAD(, map_node) sense_maps;
SLIST_HEAD(, scb) free_scbs; /*
SLIST_HEAD(, sg_map_node) sg_maps;
SLIST_HEAD(path_list, path_entry);
SLIST_HEAD(scope_list, scope);
typedef SLIST_HEAD(symlist, symbol_node) symlist_t;