/* * The callout structure is for * a routine arranging * to be called by the clock interrupt * (clock.c) with a specified argument, * in a specified amount of time. * Used, for example, to time tab * delays on typewriters. */struct	callo{	int	c_time;		/* incremental time */	caddr_t	c_arg;		/* argument to routine */	int	(*c_func)();	/* routine */};struct	callo	callout[NCALL];