char *prompt;
const char *prompt;
pack_letter(prompt, mask)	char *prompt;	unsigned short mask;{	short ch;	unsigned short tmask = mask;	if (!mask_pack(&rogue.pack, mask)) {		messagef(0, "nothing appropriate");		return(CANCEL);	}	for (;;) {		messagef(0, "%s", prompt);		for (;;) {			ch = rgetchar();			if (!is_pack_letter(&ch, &mask)) {				beep();			} else {				break;			}		}		if (ch == LIST) {			check_message();			mask = tmask;			inventory(&rogue.pack, mask);		} else {			break;		}		mask = tmask;	}	check_message();	return(ch);}