for (i = 1; i < objc - 1; i += 2) {
	if (Tcl_GetIndexFromObj(interp, objv[i], optStrings, "option",
		TCL_EXACT, &index) != TCL_OK) {
	    return TCL_ERROR;
	}
	switch (index) {
	case OPT_MAXLEN:
	    if (Tcl_GetSizeIntFromObj(interp, objv[i + 1], &maxlen) != TCL_OK) {
	    if (TclGetSizeIntFromObj(interp, objv[i + 1], &maxlen) != TCL_OK) {
		return TCL_ERROR;
	    }
	    if (maxlen < 0) {
		Tcl_SetObjResult(interp, Tcl_NewStringObj(
			"line length out of range", -1));
		Tcl_SetErrorCode(interp, "TCL", "BINARY", "ENCODE",
			"LINE_LENGTH", NULL);