int SetCharacterClassRange (low, high, value) register int low, high;		 register int value;
int SetCharacterClassRange ( register int low,		 	 register int high, register int value)
int SetCharacterClassRange (low, high, value)    register int low, high;		/* in range of [0..255] */    register int value;			/* arbitrary */{    if (low < 0 || high > 255 || high < low) return (-1);    for (; low <= high; low++) charClass[low] = value;    return (0);}