register DateInfo *info,
			    Tcl_Obj *strObj, ClockFmtScnCmdArgs *opts);
static int		ClockCalcRelTime(
			    register DateInfo *info, ClockFmtScnCmdArgs *opts);
static int		ClockAddObjCmd(
			    ClientData clientData, Tcl_Interp *interp,
			    int objc, Tcl_Obj *const objv[]);
static int		ClockValidDate(
			    ClientData, register DateInfo *,
			    register ClockFmtScnCmdArgs *);
static struct tm *	ThreadSafeLocalTime(const time_t *);
static size_t		TzsetIfNecessary(void);
static void		ClockDeleteCmdProc(ClientData);

/*
 * Structure containing description of "native" clock commands to create.
 */

	if (yydate.julianDay > 5373484) {
	    Tcl_SetObjResult(opts->interp, Tcl_NewStringObj(
		"requested date too large to represent", -1));
	    Tcl_SetErrorCode(opts->interp, "CLOCK", "dateTooLarge", NULL);
	    return TCL_ERROR;
	}
    }

    /* Apply validation rules, if expected */
    if ( (opts->flags & CLF_VALIDATE) ) {
	if (ClockValidDate(clientData, info, opts) != TCL_OK) {
	    return TCL_ERROR;
	}
    }

    /* Local seconds to UTC (stored in yydate.seconds) */

    if (info->flags & (CLF_ASSEMBLE_SECONDS|CLF_ASSEMBLE_JULIANDAY)) {
	yydate.localSeconds =
	    -210866803200L
	    + ( SECONDS_PER_DAY * (Tcl_WideInt)yydate.julianDay )

    /* Increment UTC seconds with relative time */

    yydate.seconds += yyRelSeconds;

    return TCL_OK;
}

/*----------------------------------------------------------------------
 *
 * ClockValidDate --
 *
 *	Validate date info structure for wrong data (e. g. out of ranges).
 *
 * Results:
 *	Returns a standard Tcl result.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
ClockValidDate(
    ClientData clientData,	/* Client data containing literal pool */
    register DateInfo  *info,	/* Clock scan info structure */
    register
    ClockFmtScnCmdArgs *opts)	/* Format, locale, timezone and base */
{
    const char *errMsg;

    //printf("yyMonth %d, yyDay %d, yyHour %d, yyMinutes %d, yySeconds %d\n", yyMonth, yyDay, yyHour, yyMinutes, yySeconds);
    
    /* first month (used later in hath) */
    if ( yyMonth < 1 || yyMonth > 12 ) {
	errMsg = "invalid month"; goto error;
    }
    /* day of month */
    if ( yyDay < 1 || yyDay > 31 ) {
	errMsg = "invalid day"; goto error;
    } else {
	const int *h = hath[IsGregorianLeapYear(&yydate)];
	if ( yyDay > h[yyMonth-1] ) {
	    errMsg = "invalid day"; goto error;
	}
    }
    /* hour */
    if ( yyHour < 0 || yyHour > ((yyMeridian == MER24) ? 24 : 12) ) {
	errMsg = "invalid time (hour)"; goto error;
    }
    /* minutes */
    if ( yyMinutes < 0 || yyMinutes > 59 ) {
	errMsg = "invalid time (minutes)"; goto error;
    }
    /* oldscan could return secondOfDay (parsedTime) -1 by invalid time (ex.: 25:00:00) */
    if (yySeconds <= -1) {
	errMsg = "invalid time"; goto error;
    }

    return TCL_OK;

  error:
    Tcl_SetObjResult(opts->interp,
	Tcl_ObjPrintf("unable to convert input string: %s", errMsg));
    Tcl_SetErrorCode(opts->interp, "CLOCK", "invInpStr", NULL);
    return TCL_ERROR;
}

/*----------------------------------------------------------------------
 *
 * ClockFreeScan --
 *
 *	Used by ClockScanObjCmd for free scanning without format.
 *