** USEFUL.H -- Some useful stuff.
/* support for bool type */
# define bitset(bit, word) ((word) & (bit))
# define ASSERT(expr, msg, parm)\
fprintf(stderr, "assertion botch: %s:%d: ", __FILE__, __LINE__);\
fprintf(stderr, msg, parm);\
# define ASSERT(expr, msg, parm)
# define SCCSID(arg) static char SccsId[] = "arg";
/* define the types of some common functions */
extern char *strcpy(), *strncpy();
extern char *strcat(), *strncat();
extern char *index(), *rindex();