The source code for Tcl is managed by fossil.  Tcl developers coordinate all
changes to the Tcl source code at

> [Tcl Source Code](https://core.tcl-lang.org/tcl/timeline)

Release Tcl 9.0.1 arises from the check-in with tag `core-9-0-1`.

## Changes since Tcl 9.0.0
 - [zlib-8.8, zlib-8.16 fail on Fedora 40, gcc 14.1.1](https://core.tcl-lang.org/tcl/tktview/73d5cb)
 - [regression in tzdata, %z instead of offset TZ-name](https://core.tcl-lang.org/tcl/tktview/2c237b)
 - [Tcl will not start properly if there is an init.tcl file in the current dir](https://core.tcl-lang.org/tcl/tktview/43c94f)
 - [clock scan of leapsecond: wrong result](https://core.tcl-lang.org/tcl/tktview/f2b5f8)
 - [clock scan "24:00", ISO-8601 compatibility](https://core.tcl-lang.org/tcl/tktview/aee9f2)
 - [install registry and dde in $INSTALL_DIR\lib always](https://core.tcl-lang.org/tcl/tktview/364bd9)
 - [cannot build .chm help file (Windows)](https://core.tcl-lang.org/tcl/tktview/bb110c)
 - [TIP 701 - Tcl_FSTildeExpand C API](https://core.tcl-lang.org/tips/doc/trunk/tip/701.md)
 - [buffer overwrite for non-BMP characters in utf-16](https://core.tcl-lang.org/tcl/tktview/66da4d)

Release Tcl 9.0.0 arises from the check-in with tag `core-9-0-0`.

\fItime\fR
.
A time of day, which is of the form:
.QW "\fIhh\fR?\fB:\fImm\fR?\fB:\fIss\fR?? ?\fImeridian\fR? ?\fIzone\fR?"
or
.QW "\fBhhmm \fR?\fBmeridian\fR? ?\fBzone\fR?" .
If no \fImeridian\fR is specified, \fIhh\fR is interpreted on
a 24-hour clock.
a 24-hour clock. The "24:00" and "24:00:00" formats (with or without
colon) are supported only if no \fImeridian\fR is specified.
.TP
\fIdate\fR
.
A specific month and day with optional year.  The
acceptable formats are
.QW "\fImm\fB/\fIdd\fR?\fB/\fIyy\fR?" ,
.QW "\fImonthname dd\fR?\fB, \fIyy\fR?" ,

.QW T ,
.QW "\fICCyymmdd hhmmss\fR" ,
.QW "\fICCyymmdd\fBT\fIhh:mm:ss\fR" ,
or
.QW "\fICCyy-mm-dd\fBT\fIhh:mm:ss\fR" .
Note that only these four formats are accepted.
The command does \fInot\fR accept the full range of point-in-time
specifications specified in ISO8601.  Other formats can be recognized by
specifications specified in ISO8601.  For example, leap seconds are
not supported. The "24:00" and "24:00:00" formats (with or without
colon) are supported.  Other formats can be recognized by
giving an explicit \fB\-format\fR option to the \fBclock scan\fR command.
.TP
\fIrelative time\fR
.
A specification relative to the current time.  The format is \fBnumber
unit\fR. Acceptable units are \fByear\fR, \fBfortnight\fR,
\fBmonth\fR, \fBweek\fR, \fBday\fR,

    DateInfo *info,		/* Clock scan info structure */
    ClockFmtScnCmdArgs *opts,	/* Scan options */
    int stage)			/* Stage to validate (1, 2 or 3 for both) */
{
    const char *errMsg = "", *errCode = "";
    TclDateFields temp;
    int tempCpyFlg = 0;
    int leapDay = -1;
    ClockClientData *dataPtr = opts->dataPtr;

#if 0
    printf("yyMonth %d, yyDay %d, yyDayOfYear %d, yyHour %d, yyMinutes %d, yySeconds %" TCL_LL_MODIFIER "d, "
	    "yySecondOfDay %" TCL_LL_MODIFIER "d, sec %" TCL_LL_MODIFIER "d, daySec %" TCL_LL_MODIFIER "d, tzOffset %d\n",
	    yyMonth, yyDay, yydate.dayOfYear, yyHour, yyMinutes, yySeconds,
	    yySecondOfDay, yydate.localSeconds, yydate.localSeconds % SECONDS_PER_DAY,

	if ((info->flags & CLF_ISO8601YEAR)) {
	    if (yydate.iso8601Year < dataPtr->validMinYear
		    || yydate.iso8601Year > dataPtr->validMaxYear) {
		errMsg = "invalid iso year";
		errCode = "iso year";
		goto error;
	    }
	    if ((yydate.iso8601Year < 1972) || (yydate.iso8601Year > 2017)) {
		leapDay = 0;
	    }
	}
	if (info->flags & CLF_YEAR) {
	    if (yyYear < dataPtr->validMinYear
		    || yyYear > dataPtr->validMaxYear) {
		errMsg = "invalid year";
		errCode = "year";
		goto error;
	    }
	    if ((yyYear < 1972) || (yyYear > 2017)) {
		leapDay = 0;
	    }
	} else if ((info->flags & CLF_ISO8601YEAR)) {
	    yyYear = yydate.iso8601Year; /* used to recognize leap */
	}
	if ((info->flags & (CLF_ISO8601YEAR | CLF_YEAR))
		== (CLF_ISO8601YEAR | CLF_YEAR)) {
	    if (yyYear != yydate.iso8601Year) {
		errMsg = "ambiguous year";
		errCode = "year";
		goto error;
	    }
	}
    }
    /* and month (used later in hath) */
    if (info->flags & CLF_MONTH) {
	if (yyMonth < 1 || yyMonth > 12) {
	    errMsg = "invalid month";
	    errCode = "month";
	    goto error;
	} else if (leapDay) {
	    switch (yyMonth) {
	    case 6:
		leapDay = 30;
		break;
	    case 12:
		leapDay = 31;
		break;
	    case 1:
	    case 7:
		leapDay = 1;
		break;
	    default:
		leapDay = 0;
		break;
	    }
	}
    }
    /* day of month */
    if (info->flags & (CLF_DAYOFMONTH|CLF_DAYOFWEEK)) {
	if (yyDay < 1 || yyDay > 31) {
	    errMsg = "invalid day";
	    errCode = "day";
	    goto error;
	} else if ((leapDay > 0) && (info->flags & CLF_DAYOFMONTH) && (yyDay != leapDay)) {
	    leapDay = 0;
	}
	if ((info->flags & CLF_MONTH)) {
	    const int *h = hath[IsGregorianLeapYear(&yydate)];

	    if (yyDay > h[yyMonth - 1]) {
		errMsg = "invalid day";
		errCode = "day";

    if (info->flags & CLF_TIME) {
	/* hour */
	if (yyHour < 0 || yyHour > ((yyMeridian == MER24) ? 24 : 12)) {
	    errMsg = "invalid time (hour)";
	    errCode = "hour";
	    goto error;
	} else if (yyHour == 24) {
	    leapDay = 0;
	}
	/* minutes */
	if (yyMinutes < 0 || yyMinutes > 59 || (yyMinutes && (yyHour == 24))) {
	    errMsg = "invalid time (minutes)";
	    errCode = "minutes";
	    goto error;
	} else if ((yyMinutes % 15) != 14) {
	    leapDay = 0;
	}
	/* oldscan could return secondOfDay (parsedTime) -1 by invalid time (ex.: 25:00:00) */
	if (yySeconds < 0 || yySeconds > (leapDay ? 60 : 59) || yySecondOfDay <= -1 || (yySeconds && (yyHour == 24))) {
	if (yySeconds < 0 || yySeconds > 59 || yySecondOfDay <= -1 || (yySeconds && (yyHour == 24))) {
	    errMsg = "invalid time";
	    errCode = "seconds";
	    goto error;
	}
    }

    if (!(stage & CLF_VALIDATE_S2) || !(opts->flags & CLF_VALIDATE_S2)) {

	}
    }
    set res; # must be empty
} -result {}
test clock-68.1a {Leap second, minute, hour [f2b5f89c0d], regression test (validity check)} -body {
    set res {}
    foreach {d i} {
	"2012-06-30 23:59:60" 1341100800
	"2012-06-30 24:00:00" 1341100800
    } {
        } {
	# check with free scan:
	if {[set t [clock scan $d -gmt 1]] != $i} {
	    lappend res "free-scan \"$d\" == $t, expected $i"
	}
	# check with formatted scan:
	if {[set t [clock scan $d -gmt 1 -format "%Y-%m-%d %H:%M:%S"]] != $i} {
	    lappend res "fmt-scan \"$d\" == $t, expected $i"
	}
    }
    set res; # must be empty
} -result {}
test clock-68.2 {Leap second, minute, hour [f2b5f89c0d], regression test (validity check)} -constraints !valid_off -body {
test clock-68.2 {Leap second, "24:00", regression test (validity check)} -constraints !valid_off -body {
    # regardless solution for [f2b5f89c0d], this conversions must fail on -valid 1 (constraints !valid_off),
    # because of wrong day and month for the leap second. There were only leap seconds from 1972 - 2016:
    # Leap seconds are not supported. "24:00" is supported.
    set res {}
    foreach {d i} {
	"2012-06-29 23:59:60" "invalid time"
	"2012-05-30 23:59:60" "invalid time"
	"2012-05-30 23:60:60" "invalid time"
	"2012-05-30 24:00:01" "invalid time"
	"2012-05-30 24:01:00" "invalid time"
	"1971-06-30 23:59:60" "invalid time"
	"2012-06-30 23:59:60" "invalid time"
	"2018-06-30 23:59:60" "invalid time"
    } {
        } {
	# check with free scan:
	if {![catch { clock scan $d -gmt 1 } t] || ![string match *$i* $t]} {
	    lappend res "free-scan \"$d\" == \"$t\", expected \"$i\""
	}
	# check with formatted scan:
	if {![catch { clock scan $d -gmt 1 -format "%Y-%m-%d %H:%M:%S" } t] || ![string match *$i* $t]} {
	    lappend res "fmt-scan \"$d\" == \"$t\", expected \"$i\""