C API: Calendar. More...

#include "unicode/utypes.h"
#include "unicode/uenum.h"
#include "unicode/uloc.h"
#include "unicode/localpointer.h"

Namespaces
	icu
	File coll.h.

Macros
#define	UCAL_UNKNOWN_ZONE_ID "Etc/Unknown"
	The time zone ID reserved for unknown time zone. More...

Typedefs
typedef void *	UCalendar
	A calendar. More...

typedef enum UCalendarType	UCalendarType

typedef enum UCalendarDateFields	UCalendarDateFields

typedef enum UCalendarDaysOfWeek	UCalendarDaysOfWeek

typedef enum UCalendarMonths	UCalendarMonths

typedef enum UCalendarAMPMs	UCalendarAMPMs

typedef enum USystemTimeZoneType	USystemTimeZoneType

typedef enum UCalendarDisplayNameType	UCalendarDisplayNameType

typedef enum UCalendarAttribute	UCalendarAttribute

typedef enum UCalendarWallTimeOption	UCalendarWallTimeOption

typedef enum UCalendarLimitType	UCalendarLimitType

typedef enum UCalendarWeekdayType	UCalendarWeekdayType

typedef enum UTimeZoneTransitionType	UTimeZoneTransitionType

Enumerations
enum	UCalendarType { UCAL_TRADITIONAL, UCAL_DEFAULT = UCAL_TRADITIONAL, UCAL_GREGORIAN }
	Possible types of UCalendars. More...

enum	UCalendarDateFields { UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET, UCAL_YEAR_WOY, UCAL_DOW_LOCAL, UCAL_EXTENDED_YEAR, UCAL_JULIAN_DAY, UCAL_MILLISECONDS_IN_DAY, UCAL_IS_LEAP_MONTH, UCAL_FIELD_COUNT, UCAL_DAY_OF_MONTH =UCAL_DATE }
	Possible fields in a UCalendar. More...

enum	UCalendarDaysOfWeek { UCAL_SUNDAY = 1, UCAL_MONDAY, UCAL_TUESDAY, UCAL_WEDNESDAY, UCAL_THURSDAY, UCAL_FRIDAY, UCAL_SATURDAY }
	Useful constant for days of week. More...

enum	UCalendarMonths { UCAL_JANUARY, UCAL_FEBRUARY, UCAL_MARCH, UCAL_APRIL, UCAL_MAY, UCAL_JUNE, UCAL_JULY, UCAL_AUGUST, UCAL_SEPTEMBER, UCAL_OCTOBER, UCAL_NOVEMBER, UCAL_DECEMBER, UCAL_UNDECIMBER }
	Possible months in a UCalendar. More...

enum	UCalendarAMPMs { UCAL_AM, UCAL_PM }
	Possible AM/PM values in a UCalendar. More...

enum	USystemTimeZoneType { UCAL_ZONE_TYPE_ANY, UCAL_ZONE_TYPE_CANONICAL, UCAL_ZONE_TYPE_CANONICAL_LOCATION }
	System time zone type constants used by filtering zones in ucal_openTimeZoneIDEnumeration. More...

enum	UCalendarDisplayNameType { UCAL_STANDARD, UCAL_SHORT_STANDARD, UCAL_DST, UCAL_SHORT_DST }
	Possible formats for a UCalendar's display name. More...

enum	UCalendarAttribute { UCAL_LENIENT, UCAL_FIRST_DAY_OF_WEEK, UCAL_MINIMAL_DAYS_IN_FIRST_WEEK, UCAL_REPEATED_WALL_TIME, UCAL_SKIPPED_WALL_TIME }
	Types of UCalendar attributes. More...

enum	UCalendarWallTimeOption { UCAL_WALLTIME_LAST, UCAL_WALLTIME_FIRST, UCAL_WALLTIME_NEXT_VALID }
	Options for handling ambiguous wall time at time zone offset transitions. More...

enum	UCalendarLimitType { UCAL_MINIMUM, UCAL_MAXIMUM, UCAL_GREATEST_MINIMUM, UCAL_LEAST_MAXIMUM, UCAL_ACTUAL_MINIMUM, UCAL_ACTUAL_MAXIMUM }
	Possible limit values for a UCalendar. More...

enum	UCalendarWeekdayType { UCAL_WEEKDAY, UCAL_WEEKEND, UCAL_WEEKEND_ONSET, UCAL_WEEKEND_CEASE }
	Weekday types, as returned by ucal_getDayOfWeekType(). More...

enum	UTimeZoneTransitionType { UCAL_TZ_TRANSITION_NEXT, UCAL_TZ_TRANSITION_NEXT_INCLUSIVE, UCAL_TZ_TRANSITION_PREVIOUS, UCAL_TZ_TRANSITION_PREVIOUS_INCLUSIVE }
	Time zone transition types for ucal_getTimeZoneTransitionDate. More...

Functions
UEnumeration *	ucal_openTimeZoneIDEnumeration (USystemTimeZoneType zoneType, const char region, const int32_t rawOffset, UErrorCode *ec)
	Create an enumeration over system time zone IDs with the given filter conditions. More...

UEnumeration *	ucal_openTimeZones (UErrorCode *ec)
	Create an enumeration over all time zones. More...

UEnumeration *	ucal_openCountryTimeZones (const char country, UErrorCode ec)
	Create an enumeration over all time zones associated with the given country. More...

int32_t	ucal_getDefaultTimeZone (UChar result, int32_t resultCapacity, UErrorCode ec)
	Return the default time zone. More...

void	ucal_setDefaultTimeZone (const UChar zoneID, UErrorCode ec)
	Set the default time zone. More...

int32_t	ucal_getHostTimeZone (UChar result, int32_t resultCapacity, UErrorCode ec)
	Return the current host time zone. More...

int32_t	ucal_getDSTSavings (const UChar zoneID, UErrorCode ec)
	Return the amount of time in milliseconds that the clock is advanced during daylight savings time for the given time zone, or zero if the time zone does not observe daylight savings time. More...

UDate	ucal_getNow (void)
	Get the current date and time. More...

UCalendar *	ucal_open (const UChar zoneID, int32_t len, const char locale, UCalendarType type, UErrorCode *status)
	Open a UCalendar. More...

void	ucal_close (UCalendar *cal)
	Close a UCalendar. More...

UCalendar *	ucal_clone (const UCalendar cal, UErrorCode status)
	Open a copy of a UCalendar. More...

void	ucal_setTimeZone (UCalendar cal, const UChar zoneID, int32_t len, UErrorCode *status)
	Set the TimeZone used by a UCalendar. More...

int32_t	ucal_getTimeZoneID (const UCalendar cal, UChar result, int32_t resultLength, UErrorCode *status)
	Get the ID of the UCalendar's time zone. More...

int32_t	ucal_getTimeZoneDisplayName (const UCalendar cal, UCalendarDisplayNameType type, const char locale, UChar result, int32_t resultLength, UErrorCode status)
	Get the display name for a UCalendar's TimeZone. More...

UBool	ucal_inDaylightTime (const UCalendar cal, UErrorCode status)
	Determine if a UCalendar is currently in daylight savings time. More...

void	ucal_setGregorianChange (UCalendar cal, UDate date, UErrorCode pErrorCode)
	Sets the GregorianCalendar change date. More...

UDate	ucal_getGregorianChange (const UCalendar cal, UErrorCode pErrorCode)
	Gets the Gregorian Calendar change date. More...

int32_t	ucal_getAttribute (const UCalendar *cal, UCalendarAttribute attr)
	Get a numeric attribute associated with a UCalendar. More...

void	ucal_setAttribute (UCalendar *cal, UCalendarAttribute attr, int32_t newValue)
	Set a numeric attribute associated with a UCalendar. More...

const char *	ucal_getAvailable (int32_t localeIndex)
	Get a locale for which calendars are available. More...

int32_t	ucal_countAvailable (void)
	Determine how many locales have calendars available. More...

UDate	ucal_getMillis (const UCalendar cal, UErrorCode status)
	Get a UCalendar's current time in millis. More...

void	ucal_setMillis (UCalendar cal, UDate dateTime, UErrorCode status)
	Set a UCalendar's current time in millis. More...

void	ucal_setDate (UCalendar cal, int32_t year, int32_t month, int32_t date, UErrorCode status)
	Set a UCalendar's current date. More...

void	ucal_setDateTime (UCalendar cal, int32_t year, int32_t month, int32_t date, int32_t hour, int32_t minute, int32_t second, UErrorCode status)
	Set a UCalendar's current date. More...

UBool	ucal_equivalentTo (const UCalendar cal1, const UCalendar cal2)
	Returns TRUE if two UCalendars are equivalent. More...

void	ucal_add (UCalendar cal, UCalendarDateFields field, int32_t amount, UErrorCode status)
	Add a specified signed amount to a particular field in a UCalendar. More...

void	ucal_roll (UCalendar cal, UCalendarDateFields field, int32_t amount, UErrorCode status)
	Add a specified signed amount to a particular field in a UCalendar. More...

int32_t	ucal_get (const UCalendar cal, UCalendarDateFields field, UErrorCode status)
	Get the current value of a field from a UCalendar. More...

void	ucal_set (UCalendar *cal, UCalendarDateFields field, int32_t value)
	Set the value of a field in a UCalendar. More...

UBool	ucal_isSet (const UCalendar *cal, UCalendarDateFields field)
	Determine if a field in a UCalendar is set. More...

void	ucal_clearField (UCalendar *cal, UCalendarDateFields field)
	Clear a field in a UCalendar. More...

void	ucal_clear (UCalendar *calendar)
	Clear all fields in a UCalendar. More...

int32_t	ucal_getLimit (const UCalendar cal, UCalendarDateFields field, UCalendarLimitType type, UErrorCode status)
	Determine a limit for a field in a UCalendar. More...

const char *	ucal_getLocaleByType (const UCalendar cal, ULocDataLocaleType type, UErrorCode status)
	Get the locale for this calendar object. More...

const char *	ucal_getTZDataVersion (UErrorCode *status)
	Returns the timezone data version currently used by ICU. More...

int32_t	ucal_getCanonicalTimeZoneID (const UChar id, int32_t len, UChar result, int32_t resultCapacity, UBool isSystemID, UErrorCode status)
	Returns the canonical system timezone ID or the normalized custom time zone ID for the given time zone ID. More...

const char *	ucal_getType (const UCalendar cal, UErrorCode status)
	Get the resource keyword value string designating the calendar type for the UCalendar. More...

UEnumeration *	ucal_getKeywordValuesForLocale (const char key, const char locale, UBool commonlyUsed, UErrorCode *status)
	Given a key and a locale, returns an array of string values in a preferred order that would make a difference. More...

UCalendarWeekdayType	ucal_getDayOfWeekType (const UCalendar cal, UCalendarDaysOfWeek dayOfWeek, UErrorCode status)
	Returns whether the given day of the week is a weekday, a weekend day, or a day that transitions from one to the other, for the locale and calendar system associated with this UCalendar (the locale's region is often the most determinant factor). More...

int32_t	ucal_getWeekendTransition (const UCalendar cal, UCalendarDaysOfWeek dayOfWeek, UErrorCode status)
	Returns the time during the day at which the weekend begins or ends in this calendar system. More...

UBool	ucal_isWeekend (const UCalendar cal, UDate date, UErrorCode status)
	Returns TRUE if the given UDate is in the weekend in this calendar system. More...

int32_t	ucal_getFieldDifference (UCalendar cal, UDate target, UCalendarDateFields field, UErrorCode status)
	Return the difference between the target time and the time this calendar object is currently set to. More...

UBool	ucal_getTimeZoneTransitionDate (const UCalendar cal, UTimeZoneTransitionType type, UDate transition, UErrorCode *status)
	Get the UDate for the next/previous time zone transition relative to the calendar's current date, in the time zone to which the calendar is currently set. More...

int32_t	ucal_getWindowsTimeZoneID (const UChar id, int32_t len, UChar winid, int32_t winidCapacity, UErrorCode *status)
	Converts a system time zone ID to an equivalent Windows time zone ID. More...

int32_t	ucal_getTimeZoneIDForWindowsID (const UChar winid, int32_t len, const char region, UChar id, int32_t idCapacity, UErrorCode status)
	Converts a Windows time zone ID to an equivalent system time zone ID for a region. More...

Detailed Description

C API: Calendar.

Calendar C API

UCalendar C API is used for converting between a UDate object and a set of integer fields such as UCAL_YEAR, UCAL_MONTH, UCAL_DAY, UCAL_HOUR, and so on. (A UDate object represents a specific instant in time with millisecond precision. See UDate for information about the UDate .)

Types of UCalendar interpret a UDate according to the rules of a specific calendar system. The U_STABLE provides the enum UCalendarType with UCAL_TRADITIONAL and UCAL_GREGORIAN.

Like other locale-sensitive C API, calendar API provides a function, ucal_open(), which returns a pointer to UCalendar whose time fields have been initialized with the current date and time. We need to specify the type of calendar to be opened and the timezoneId.

UCalendar *caldef;
UChar *tzId;
UErrorCode status;
tzId=(UChar*)malloc(sizeof(UChar) * (strlen("PST") +1) );
u_uastrcpy(tzId, "PST");
caldef=ucal_open(tzID, u_strlen(tzID), NULL, UCAL_TRADITIONAL, &status);

A UCalendar object can produce all the time field values needed to implement the date-time formatting for a particular language and calendar style (for example, Japanese-Gregorian, Japanese-Traditional).

When computing a UDate from time fields, two special circumstances may arise: there may be insufficient information to compute the UDate (such as only year and month but no day in the month), or there may be inconsistent information (such as "Tuesday, July 15, 1996" – July 15, 1996 is actually a Monday).

Insufficient information. The calendar will use default information to specify the missing fields. This may vary by calendar; for the Gregorian calendar, the default for a field is the same as that of the start of the epoch: i.e., UCAL_YEAR = 1970, UCAL_MONTH = JANUARY, UCAL_DATE = 1, etc.

Inconsistent information. If fields conflict, the calendar will give preference to fields set more recently. For example, when determining the day, the calendar will look for one of the following combinations of fields. The most recent combination, as determined by the most recently set single field, will be used.

UCAL_MONTH + UCAL_DAY_OF_MONTH
UCAL_MONTH + UCAL_WEEK_OF_MONTH + UCAL_DAY_OF_WEEK
UCAL_MONTH + UCAL_DAY_OF_WEEK_IN_MONTH + UCAL_DAY_OF_WEEK
UCAL_DAY_OF_YEAR
UCAL_DAY_OF_WEEK + UCAL_WEEK_OF_YEAR

For the time of day:

UCAL_HOUR_OF_DAY
UCAL_AM_PM + UCAL_HOUR

Note: for some non-Gregorian calendars, different fields may be necessary for complete disambiguation. For example, a full specification of the historical Arabic astronomical calendar requires year, month, day-of-month and day-of-week in some cases.

Note: There are certain possible ambiguities in interpretation of certain singular times, which are resolved in the following ways:

24:00:00 "belongs" to the following day. That is, 23:59 on Dec 31, 1969 < 24:00 on Jan 1, 1970 < 24:01:00 on Jan 1, 1970
Although historically not precise, midnight also belongs to "am", and noon belongs to "pm", so on the same day, 12:00 am (midnight) < 12:01 am, and 12:00 pm (noon) < 12:01 pm

The date or time format strings are not part of the definition of a calendar, as those must be modifiable or overridable by the user at runtime. Use icu::DateFormat to format dates.

Calendar provides an API for field "rolling", where fields can be incremented or decremented, but wrap around. For example, rolling the month up in the date December 12, 1996 results in January 12, 1996.

Calendar also provides a date arithmetic function for adding the specified (signed) amount of time to a particular time field. For example, subtracting 5 days from the date September 12, 1996 results in September 7, 1996.

The Japanese calendar uses a combination of era name and year number. When an emperor of Japan abdicates and a new emperor ascends the throne, a new era is declared and year number is reset to 1. Even if the date of abdication is scheduled ahead of time, the new era name might not be announced until just before the date. In such case, ICU4C may include a start date of future era without actual era name, but not enabled by default. ICU4C users who want to test the behavior of the future era can enable the tentative era by:

Environment variable ICU_ENABLE_TENTATIVE_ERA=true.

Stable:: ICU 2.0

Definition in file ucal.h.

Macro Definition Documentation

◆ UCAL_UNKNOWN_ZONE_ID

#define UCAL_UNKNOWN_ZONE_ID "Etc/Unknown"

The time zone ID reserved for unknown time zone.

It behaves like the GMT/UTC time zone but has the special ID "Etc/Unknown".

Stable:: ICU 4.8

Definition at line 163 of file ucal.h.

Typedef Documentation

◆ UCalendar

typedef void* UCalendar

A calendar.

For usage in C programs.

Stable:: ICU 2.0

Definition at line 169 of file ucal.h.

◆ UCalendarAMPMs

typedef enum UCalendarAMPMs UCalendarAMPMs

Stable:: ICU 2.0

Definition at line 542 of file ucal.h.

◆ UCalendarAttribute

typedef enum UCalendarAttribute UCalendarAttribute

Stable:: ICU 2.0

Definition at line 959 of file ucal.h.

◆ UCalendarDateFields

typedef enum UCalendarDateFields UCalendarDateFields

Stable:: ICU 2.0

Definition at line 464 of file ucal.h.

◆ UCalendarDaysOfWeek

typedef enum UCalendarDaysOfWeek UCalendarDaysOfWeek

Stable:: ICU 2.0

Definition at line 491 of file ucal.h.

◆ UCalendarDisplayNameType

typedef enum UCalendarDisplayNameType UCalendarDisplayNameType

Stable:: ICU 2.0

Definition at line 843 of file ucal.h.

◆ UCalendarLimitType

typedef enum UCalendarLimitType UCalendarLimitType

Stable:: ICU 2.0

Definition at line 1302 of file ucal.h.

◆ UCalendarMonths

typedef enum UCalendarMonths UCalendarMonths

Stable:: ICU 2.0

Definition at line 529 of file ucal.h.

◆ UCalendarType

typedef enum UCalendarType UCalendarType

Stable:: ICU 2.0

Definition at line 194 of file ucal.h.

◆ UCalendarWallTimeOption

typedef enum UCalendarWallTimeOption UCalendarWallTimeOption

Stable:: ICU 49

Definition at line 989 of file ucal.h.

◆ UCalendarWeekdayType

typedef enum UCalendarWeekdayType UCalendarWeekdayType

Stable:: ICU 4.4

Definition at line 1426 of file ucal.h.

◆ USystemTimeZoneType

typedef enum USystemTimeZoneType USystemTimeZoneType

Stable:: ICU 4.8

Definition at line 569 of file ucal.h.

◆ UTimeZoneTransitionType

typedef enum UTimeZoneTransitionType UTimeZoneTransitionType

Stable:: ICU 50

Definition at line 1540 of file ucal.h.

Enumeration Type Documentation

◆ UCalendarAMPMs

enum UCalendarAMPMs

Possible AM/PM values in a UCalendar.

Stable:: ICU 2.0

Enumerator
UCAL_AM	AM.
UCAL_PM	PM.

Definition at line 534 of file ucal.h.

◆ UCalendarAttribute

enum UCalendarAttribute

Types of UCalendar attributes.

Stable:: ICU 2.0

Enumerator
UCAL_LENIENT	Lenient parsing. Stable: ICU 2.0
UCAL_FIRST_DAY_OF_WEEK	First day of week. Stable: ICU 2.0
UCAL_MINIMAL_DAYS_IN_FIRST_WEEK	Minimum number of days in first week. Stable: ICU 2.0
UCAL_REPEATED_WALL_TIME	The behavior for handling wall time repeating multiple times at negative time zone offset transitions. Stable: ICU 49
UCAL_SKIPPED_WALL_TIME	The behavior for handling skipped wall time at positive time zone offset transitions. Stable: ICU 49

Definition at line 928 of file ucal.h.

◆ UCalendarDateFields

enum UCalendarDateFields

Possible fields in a UCalendar.

Stable:: ICU 2.0

Enumerator
UCAL_ERA	Field number indicating the era, e.g., AD or BC in the Gregorian (Julian) calendar. This is a calendar-specific value. Stable: ICU 2.6
UCAL_YEAR	Field number indicating the year. This is a calendar-specific value. Stable: ICU 2.6
UCAL_MONTH	Field number indicating the month. This is a calendar-specific value. The first month of the year is `JANUARY`; the last depends on the number of months in a year. See also UCAL_JANUARY UCAL_FEBRUARY UCAL_MARCH UCAL_APRIL UCAL_MAY UCAL_JUNE UCAL_JULY UCAL_AUGUST UCAL_SEPTEMBER UCAL_OCTOBER UCAL_NOVEMBER UCAL_DECEMBER UCAL_UNDECIMBER Stable: ICU 2.6
UCAL_WEEK_OF_YEAR	Field number indicating the week number within the current year. The first week of the year, as defined by `UCAL_FIRST_DAY_OF_WEEK` and `UCAL_MINIMAL_DAYS_IN_FIRST_WEEK` attributes, has value 1. Subclasses define the value of `UCAL_WEEK_OF_YEAR` for days before the first week of the year. See also ucal_getAttribute ucal_setAttribute Stable: ICU 2.6
UCAL_WEEK_OF_MONTH	Field number indicating the week number within the current month. The first week of the month, as defined by `UCAL_FIRST_DAY_OF_WEEK` and `UCAL_MINIMAL_DAYS_IN_FIRST_WEEK` attributes, has value 1. Subclasses define the value of `WEEK_OF_MONTH` for days before the first week of the month. See also ucal_getAttribute ucal_setAttribute UCAL_FIRST_DAY_OF_WEEK UCAL_MINIMAL_DAYS_IN_FIRST_WEEK Stable: ICU 2.6
UCAL_DATE	Field number indicating the day of the month. This is a synonym for `DAY_OF_MONTH`. The first day of the month has value 1. See also UCAL_DAY_OF_MONTH Stable: ICU 2.6
UCAL_DAY_OF_YEAR	Field number indicating the day number within the current year. The first day of the year has value 1. Stable: ICU 2.6
UCAL_DAY_OF_WEEK	Field number indicating the day of the week. This field takes values `SUNDAY`, `MONDAY`, `TUESDAY`, `WEDNESDAY`, `THURSDAY`, `FRIDAY`, and `SATURDAY`. See also UCAL_SUNDAY UCAL_MONDAY UCAL_TUESDAY UCAL_WEDNESDAY UCAL_THURSDAY UCAL_FRIDAY UCAL_SATURDAY Stable: ICU 2.6
UCAL_DAY_OF_WEEK_IN_MONTH	Field number indicating the ordinal number of the day of the week within the current month. Together with the `DAY_OF_WEEK` field, this uniquely specifies a day within a month. Unlike `WEEK_OF_MONTH` and `WEEK_OF_YEAR`, this field's value does not depend on `getFirstDayOfWeek()` or `getMinimalDaysInFirstWeek()`. `DAY_OF_MONTH 1` through `7` always correspond to `DAY_OF_WEEK_IN_MONTH 1`; `8` through `15` correspond to `DAY_OF_WEEK_IN_MONTH 2`, and so on. `DAY_OF_WEEK_IN_MONTH 0` indicates the week before `DAY_OF_WEEK_IN_MONTH 1`. Negative values count back from the end of the month, so the last Sunday of a month is specified as `DAY_OF_WEEK = SUNDAY, DAY_OF_WEEK_IN_MONTH = -1`. Because negative values count backward they will usually be aligned differently within the month than positive values. For example, if a month has 31 days, `DAY_OF_WEEK_IN_MONTH -1` will overlap `DAY_OF_WEEK_IN_MONTH 5` and the end of `4`. See also UCAL_DAY_OF_WEEK UCAL_WEEK_OF_MONTH Stable: ICU 2.6
UCAL_AM_PM	Field number indicating whether the `HOUR` is before or after noon. E.g., at 10:04:15.250 PM the `AM_PM` is `PM`. See also UCAL_AM UCAL_PM UCAL_HOUR Stable: ICU 2.6
UCAL_HOUR	Field number indicating the hour of the morning or afternoon. `HOUR` is used for the 12-hour clock. E.g., at 10:04:15.250 PM the `HOUR` is 10. See also UCAL_AM_PM UCAL_HOUR_OF_DAY Stable: ICU 2.6
UCAL_HOUR_OF_DAY	Field number indicating the hour of the day. `HOUR_OF_DAY` is used for the 24-hour clock. E.g., at 10:04:15.250 PM the `HOUR_OF_DAY` is 22. See also UCAL_HOUR Stable: ICU 2.6
UCAL_MINUTE	Field number indicating the minute within the hour. E.g., at 10:04:15.250 PM the `UCAL_MINUTE` is 4. Stable: ICU 2.6
UCAL_SECOND	Field number indicating the second within the minute. E.g., at 10:04:15.250 PM the `UCAL_SECOND` is 15. Stable: ICU 2.6
UCAL_MILLISECOND	Field number indicating the millisecond within the second. E.g., at 10:04:15.250 PM the `UCAL_MILLISECOND` is 250. Stable: ICU 2.6
UCAL_ZONE_OFFSET	Field number indicating the raw offset from GMT in milliseconds. Stable: ICU 2.6
UCAL_DST_OFFSET	Field number indicating the daylight savings offset in milliseconds. Stable: ICU 2.6
UCAL_YEAR_WOY	Field number indicating the extended year corresponding to the `UCAL_WEEK_OF_YEAR` field. This may be one greater or less than the value of `UCAL_EXTENDED_YEAR`. Stable: ICU 2.6
UCAL_DOW_LOCAL	Field number indicating the localized day of week. This will be a value from 1 to 7 inclusive, with 1 being the localized first day of the week. Stable: ICU 2.6
UCAL_EXTENDED_YEAR	Year of this calendar system, encompassing all supra-year fields. For example, in Gregorian/Julian calendars, positive Extended Year values indicate years AD, 1 BC = 0 extended, 2 BC = -1 extended, and so on. Stable: ICU 2.8
UCAL_JULIAN_DAY	Field number indicating the modified Julian day number. This is different from the conventional Julian day number in two regards. First, it demarcates days at local zone midnight, rather than noon GMT. Second, it is a local number; that is, it depends on the local time zone. It can be thought of as a single number that encompasses all the date-related fields. Stable: ICU 2.8
UCAL_MILLISECONDS_IN_DAY	Ranges from 0 to 23:59:59.999 (regardless of DST). This field behaves exactly like a composite of all time-related fields, not including the zone fields. As such, it also reflects discontinuities of those fields on DST transition days. On a day of DST onset, it will jump forward. On a day of DST cessation, it will jump backward. This reflects the fact that it must be combined with the DST_OFFSET field to obtain a unique local time value. Stable: ICU 2.8
UCAL_IS_LEAP_MONTH	Whether or not the current month is a leap month (0 or 1). See the Chinese calendar for an example of this.
UCAL_FIELD_COUNT	One more than the highest normal UCalendarDateFields value. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
UCAL_DAY_OF_MONTH	Field number indicating the day of the month. This is a synonym for `UCAL_DATE`. The first day of the month has value 1. See also UCAL_DATE Synonym for UCAL_DATE Stable: ICU 2.8

Definition at line 199 of file ucal.h.

◆ UCalendarDaysOfWeek

enum UCalendarDaysOfWeek

Useful constant for days of week.

Note: Calendar day-of-week is 1-based. Clients who create locale resources for the field of first-day-of-week should be aware of this. For instance, in US locale, first-day-of-week is set to 1, i.e., UCAL_SUNDAY. Possible days of the week in a UCalendar

Stable:: ICU 2.0

Enumerator
UCAL_SUNDAY	Sunday.
UCAL_MONDAY	Monday.
UCAL_TUESDAY	Tuesday.
UCAL_WEDNESDAY	Wednesday.
UCAL_THURSDAY	Thursday.
UCAL_FRIDAY	Friday.
UCAL_SATURDAY	Saturday.

Definition at line 473 of file ucal.h.

◆ UCalendarDisplayNameType

enum UCalendarDisplayNameType

Possible formats for a UCalendar's display name.

Stable:: ICU 2.0

Enumerator
UCAL_STANDARD	Standard display name.
UCAL_SHORT_STANDARD	Short standard display name.
UCAL_DST	Daylight savings display name.
UCAL_SHORT_DST	Short daylight savings display name.

Definition at line 831 of file ucal.h.

◆ UCalendarLimitType

enum UCalendarLimitType

Possible limit values for a UCalendar.

Stable:: ICU 2.0

Enumerator
UCAL_MINIMUM	Minimum value.
UCAL_MAXIMUM	Maximum value.
UCAL_GREATEST_MINIMUM	Greatest minimum value.
UCAL_LEAST_MAXIMUM	Leaest maximum value.
UCAL_ACTUAL_MINIMUM	Actual minimum value.
UCAL_ACTUAL_MAXIMUM	Actual maximum value.

Definition at line 1286 of file ucal.h.

◆ UCalendarMonths

enum UCalendarMonths

Possible months in a UCalendar.

Note: Calendar month is 0-based.

Stable:: ICU 2.0

Enumerator
UCAL_JANUARY	January.
UCAL_FEBRUARY	February.
UCAL_MARCH	March.
UCAL_APRIL	April.
UCAL_MAY	May.
UCAL_JUNE	June.
UCAL_JULY	July.
UCAL_AUGUST	August.
UCAL_SEPTEMBER	September.
UCAL_OCTOBER	October.
UCAL_NOVEMBER	November.
UCAL_DECEMBER	December.
UCAL_UNDECIMBER	Value of the `UCAL_MONTH` field indicating the thirteenth month of the year. Although the Gregorian calendar does not use this value, lunar calendars do.

Definition at line 496 of file ucal.h.

◆ UCalendarType

enum UCalendarType

Possible types of UCalendars.

Stable:: ICU 2.0

Enumerator

UCAL_TRADITIONAL

Despite the name, UCAL_TRADITIONAL designates the locale's default calendar, which may be the Gregorian calendar or some other calendar.

Stable:: ICU 2.0

UCAL_DEFAULT

A better name for UCAL_TRADITIONAL.

Stable:: ICU 4.2

UCAL_GREGORIAN

Unambiguously designates the Gregorian calendar for the locale.

Stable:: ICU 2.0

Definition at line 174 of file ucal.h.

◆ UCalendarWallTimeOption

enum UCalendarWallTimeOption

Options for handling ambiguous wall time at time zone offset transitions.

Stable:: ICU 49

Enumerator

UCAL_WALLTIME_LAST

An ambiguous wall time to be interpreted as the latest.

This option is valid for UCAL_REPEATED_WALL_TIME and UCAL_SKIPPED_WALL_TIME.

Stable:: ICU 49

UCAL_WALLTIME_FIRST

An ambiguous wall time to be interpreted as the earliest.

This option is valid for UCAL_REPEATED_WALL_TIME and UCAL_SKIPPED_WALL_TIME.

Stable:: ICU 49

UCAL_WALLTIME_NEXT_VALID

An ambiguous wall time to be interpreted as the next valid wall time.

This option is valid for UCAL_SKIPPED_WALL_TIME.

Stable:: ICU 49

Definition at line 966 of file ucal.h.

◆ UCalendarWeekdayType

enum UCalendarWeekdayType

Weekday types, as returned by ucal_getDayOfWeekType().

Stable:: ICU 4.4

Enumerator
UCAL_WEEKDAY	Designates a full weekday (no part of the day is included in the weekend). Stable: ICU 4.4
UCAL_WEEKEND	Designates a full weekend day (the entire day is included in the weekend). Stable: ICU 4.4
UCAL_WEEKEND_ONSET	Designates a day that starts as a weekday and transitions to the weekend. Call ucal_getWeekendTransition() to get the time of transition. Stable: ICU 4.4
UCAL_WEEKEND_CEASE	Designates a day that starts as the weekend and transitions to a weekday. Call ucal_getWeekendTransition() to get the time of transition. Stable: ICU 4.4

Definition at line 1400 of file ucal.h.

◆ USystemTimeZoneType

enum USystemTimeZoneType

System time zone type constants used by filtering zones in ucal_openTimeZoneIDEnumeration.

See also: ucal_openTimeZoneIDEnumeration

Stable:: ICU 4.8

Enumerator

UCAL_ZONE_TYPE_ANY

Any system zones.

Stable:: ICU 4.8

UCAL_ZONE_TYPE_CANONICAL

Canonical system zones.

Stable:: ICU 4.8

UCAL_ZONE_TYPE_CANONICAL_LOCATION

Canonical system zones associated with actual locations.

Stable:: ICU 4.8

Definition at line 550 of file ucal.h.

◆ UTimeZoneTransitionType

enum UTimeZoneTransitionType

Time zone transition types for ucal_getTimeZoneTransitionDate.

Stable:: ICU 50

Enumerator
UCAL_TZ_TRANSITION_NEXT	Get the next transition after the current date, i.e. excludes the current date Stable: ICU 50
UCAL_TZ_TRANSITION_NEXT_INCLUSIVE	Get the next transition on or after the current date, i.e. may include the current date Stable: ICU 50
UCAL_TZ_TRANSITION_PREVIOUS	Get the previous transition before the current date, i.e. excludes the current date Stable: ICU 50
UCAL_TZ_TRANSITION_PREVIOUS_INCLUSIVE	Get the previous transition on or before the current date, i.e. may include the current date Stable: ICU 50

Definition at line 1513 of file ucal.h.

Function Documentation

◆ ucal_add()

void ucal_add	(	UCalendar *	cal,
		UCalendarDateFields	field,
		int32_t	amount,
		UErrorCode *	status
	)

Add a specified signed amount to a particular field in a UCalendar.

This can modify more significant fields in the calendar. Adding a positive value always means moving forward in time, so for the Gregorian calendar, starting with 100 BC and adding +1 to year results in 99 BC (even though this actually reduces the numeric value of the field itself).

Parameters

cal	The UCalendar to which to add.
field	The field to which to add the signed value; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
amount	The signed amount to add to field. If the amount causes the value to exceed to maximum or minimum values for that field, other fields are modified to preserve the magnitude of the change.
status	A pointer to an UErrorCode to receive any errors

See also: ucal_roll

Stable:: ICU 2.0

◆ ucal_clear()

void ucal_clear ( UCalendar * calendar )

Clear all fields in a UCalendar.

All fields are represented as 32-bit integers.

Parameters

calendar The UCalendar to clear.

See also: ucal_get; ucal_set; ucal_isSet; ucal_clearField

Stable:: ICU 2.0

◆ ucal_clearField()

void ucal_clearField	(	UCalendar *	cal,
		UCalendarDateFields	field
	)

Clear a field in a UCalendar.

All fields are represented as 32-bit integers.

Parameters

cal	The UCalendar containing the field to clear.
field	The field to clear; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.

See also: ucal_get; ucal_set; ucal_isSet; ucal_clear

Stable:: ICU 2.0

◆ ucal_clone()

UCalendar* ucal_clone	(	const UCalendar *	cal,
		UErrorCode *	status
	)

Open a copy of a UCalendar.

This function performs a deep copy.

Parameters

cal	The calendar to copy
status	A pointer to an UErrorCode to receive any errors.

Returns: A pointer to a UCalendar identical to cal.

Stable:: ICU 4.0

◆ ucal_close()

void ucal_close ( UCalendar * cal )

Close a UCalendar.

Once closed, a UCalendar may no longer be used.

Parameters

cal	The UCalendar to close.

Stable:: ICU 2.0

◆ ucal_countAvailable()

int32_t ucal_countAvailable ( void )

Determine how many locales have calendars available.

This function is most useful as determining the loop ending condition for calls to ucal_getAvailable.

Returns: The number of locales for which calendars are available.

See also: ucal_getAvailable

Stable:: ICU 2.0

◆ ucal_equivalentTo()

UBool ucal_equivalentTo	(	const UCalendar *	cal1,
		const UCalendar *	cal2
	)

Returns TRUE if two UCalendars are equivalent.

Equivalent UCalendars will behave identically, but they may be set to different times.

Parameters

cal1	The first of the UCalendars to compare.
cal2	The second of the UCalendars to compare.

Returns: TRUE if cal1 and cal2 are equivalent, FALSE otherwise.

Stable:: ICU 2.0

◆ ucal_get()

int32_t ucal_get	(	const UCalendar *	cal,
		UCalendarDateFields	field,
		UErrorCode *	status
	)

Get the current value of a field from a UCalendar.

All fields are represented as 32-bit integers.

Parameters

cal	The UCalendar to query.
field	The desired field; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
status	A pointer to an UErrorCode to receive any errors

Returns: The value of the desired field.

See also: ucal_set; ucal_isSet; ucal_clearField; ucal_clear

Stable:: ICU 2.0

◆ ucal_getAttribute()

int32_t ucal_getAttribute	(	const UCalendar *	cal,
		UCalendarAttribute	attr
	)

Get a numeric attribute associated with a UCalendar.

Numeric attributes include the first day of the week, or the minimal numbers of days in the first week of the month.

Parameters

cal	The UCalendar to query.
attr	The desired attribute; one of UCAL_LENIENT, UCAL_FIRST_DAY_OF_WEEK, UCAL_MINIMAL_DAYS_IN_FIRST_WEEK, UCAL_REPEATED_WALL_TIME or UCAL_SKIPPED_WALL_TIME

Returns: The value of attr.

See also: ucal_setAttribute

Stable:: ICU 2.0

◆ ucal_getAvailable()

const char* ucal_getAvailable ( int32_t localeIndex )

Get a locale for which calendars are available.

A UCalendar in a locale returned by this function will contain the correct day and month names for the locale.

Parameters

localeIndex The index of the desired locale.

Returns: A locale for which calendars are available, or 0 if none.

See also: ucal_countAvailable

Stable:: ICU 2.0

◆ ucal_getCanonicalTimeZoneID()

int32_t ucal_getCanonicalTimeZoneID	(	const UChar *	id,
		int32_t	len,
		UChar *	result,
		int32_t	resultCapacity,
		UBool *	isSystemID,
		UErrorCode *	status
	)

Returns the canonical system timezone ID or the normalized custom time zone ID for the given time zone ID.

Parameters

id	The input timezone ID to be canonicalized.
len	The length of id, or -1 if null-terminated.
result	The buffer receives the canonical system timezone ID or the custom timezone ID in normalized format.
resultCapacity	The capacity of the result buffer.
isSystemID	Receives if the given ID is a known system timezone ID.
status	Receives the status. When the given timezone ID is neither a known system time zone ID nor a valid custom timezone ID, U_ILLEGAL_ARGUMENT_ERROR is set.

Returns: The result string length, not including the terminating null.

Stable:: ICU 4.0

◆ ucal_getDayOfWeekType()

UCalendarWeekdayType ucal_getDayOfWeekType	(	const UCalendar *	cal,
		UCalendarDaysOfWeek	dayOfWeek,
		UErrorCode *	status
	)

Returns whether the given day of the week is a weekday, a weekend day, or a day that transitions from one to the other, for the locale and calendar system associated with this UCalendar (the locale's region is often the most determinant factor).

If a transition occurs at midnight, then the days before and after the transition will have the type UCAL_WEEKDAY or UCAL_WEEKEND. If a transition occurs at a time other than midnight, then the day of the transition will have the type UCAL_WEEKEND_ONSET or UCAL_WEEKEND_CEASE. In this case, the function ucal_getWeekendTransition() will return the point of transition.

Parameters

cal	The UCalendar to query.
dayOfWeek	The day of the week whose type is desired (UCAL_SUNDAY..UCAL_SATURDAY).
status	The error code for the operation.

Returns: The UCalendarWeekdayType for the day of the week.

Stable:: ICU 4.4

◆ ucal_getDefaultTimeZone()

int32_t ucal_getDefaultTimeZone	(	UChar *	result,
		int32_t	resultCapacity,
		UErrorCode *	ec
	)

Return the default time zone.

The default is determined initially by querying the host operating system. If the host system detection routines fail, or if they specify a TimeZone or TimeZone offset which is not recognized, then the special TimeZone "Etc/Unknown" is returned.

The default may be changed with ucal_setDefaultTimeZone() or with the C++ TimeZone API, TimeZone::adoptDefault(TimeZone*).

Parameters

result	A buffer to receive the result, or NULL
resultCapacity	The capacity of the result buffer
ec	input/output error code

Returns: The result string length, not including the terminating null

See also: UCAL_UNKNOWN_ZONE_ID

Stable:: ICU 2.6

◆ ucal_getDSTSavings()

int32_t ucal_getDSTSavings	(	const UChar *	zoneID,
		UErrorCode *	ec
	)

Return the amount of time in milliseconds that the clock is advanced during daylight savings time for the given time zone, or zero if the time zone does not observe daylight savings time.

Parameters

zoneID	null-terminated time zone ID
ec	input/output error code

Returns: the number of milliseconds the time is advanced with respect to standard time when the daylight savings rules are in effect. This is always a non-negative number, most commonly either 3,600,000 (one hour) or zero.

Stable:: ICU 2.6

◆ ucal_getFieldDifference()

int32_t ucal_getFieldDifference	(	UCalendar *	cal,
		UDate	target,
		UCalendarDateFields	field,
		UErrorCode *	status
	)

Return the difference between the target time and the time this calendar object is currently set to.

If the target time is after the current calendar setting, the the returned value will be positive. The field parameter specifies the units of the return value. For example, if field is UCAL_MONTH and ucal_getFieldDifference returns 3, then the target time is 3 to less than 4 months after the current calendar setting.

As a side effect of this call, this calendar is advanced toward target by the given amount. That is, calling this function has the side effect of calling ucal_add on this calendar with the specified field and an amount equal to the return value from this function.

A typical way of using this function is to call it first with the largest field of interest, then with progressively smaller fields.

Parameters

cal	The UCalendar to compare and update.
target	The target date to compare to the current calendar setting.
field	The field to compare; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
status	A pointer to an UErrorCode to receive any errors

Returns: The date difference for the specified field.

Stable:: ICU 4.8

◆ ucal_getGregorianChange()

UDate ucal_getGregorianChange	(	const UCalendar *	cal,
		UErrorCode *	pErrorCode
	)

Gets the Gregorian Calendar change date.

This is the point when the switch from Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October 15, 1582. Previous to this time and date will be Julian dates.

This function works only for Gregorian calendars. If the UCalendar is not an instance of a Gregorian calendar, then a U_UNSUPPORTED_ERROR error code is set.

Parameters

cal	The calendar object.
pErrorCode	Pointer to a standard ICU error code. Its input value must pass the U_SUCCESS() test, or else the function returns immediately. Check for U_FAILURE() on output or use with function chaining. (See User Guide for details.)

Returns: The Gregorian cutover time for this calendar.

See also: GregorianCalendar::getGregorianChange; ucal_setGregorianChange

Stable:: ICU 3.6

◆ ucal_getHostTimeZone()

int32_t ucal_getHostTimeZone	(	UChar *	result,
		int32_t	resultCapacity,
		UErrorCode *	ec
	)

Return the current host time zone.

The host time zone is detected from the current host system configuration by querying the host operating system. If the host system detection routines fail, or if they specify a TimeZone or TimeZone offset which is not recognized, then the special TimeZone "Etc/Unknown" is returned.

Note that host time zone and the ICU default time zone can be different.

The ICU default time zone does not change once initialized unless modified by calling ucal_setDefaultTimeZone() or with the C++ TimeZone API, TimeZone::adoptDefault(TimeZone*).

If the host operating system configuration has changed since ICU has initialized then the returned value can be different than the ICU default time zone, even if the default has not changed.

This function is not thread safe.

Parameters

result	A buffer to receive the result, or NULL
resultCapacity	The capacity of the result buffer
ec	input/output error code

Returns: The result string length, not including the terminating null

See also: UCAL_UNKNOWN_ZONE_ID

Draft:: This API may be changed in the future versions and was introduced in ICU 65

◆ ucal_getKeywordValuesForLocale()

UEnumeration* ucal_getKeywordValuesForLocale	(	const char *	key,
		const char *	locale,
		UBool	commonlyUsed,
		UErrorCode *	status
	)

Given a key and a locale, returns an array of string values in a preferred order that would make a difference.

These are all and only those values where the open (creation) of the service with the locale formed from the input locale plus input keyword and that value has different behavior than creation with the input locale alone.

Parameters

key	one of the keys supported by this service. For now, only "calendar" is supported.
locale	the locale
commonlyUsed	if set to true it will return only commonly used values with the given locale in preferred order. Otherwise, it will return all the available values for the locale.
status	error status

Returns: a string enumeration over keyword values for the given key and the locale.

Stable:: ICU 4.2

◆ ucal_getLimit()

int32_t ucal_getLimit	(	const UCalendar *	cal,
		UCalendarDateFields	field,
		UCalendarLimitType	type,
		UErrorCode *	status
	)

Determine a limit for a field in a UCalendar.

A limit is a maximum or minimum value for a field.

Parameters

cal	The UCalendar to query.
field	The desired field; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
type	The desired critical point; one of UCAL_MINIMUM, UCAL_MAXIMUM, UCAL_GREATEST_MINIMUM, UCAL_LEAST_MAXIMUM, UCAL_ACTUAL_MINIMUM, UCAL_ACTUAL_MAXIMUM
status	A pointer to an UErrorCode to receive any errors.

Returns: The requested value.

Stable:: ICU 2.0

◆ ucal_getLocaleByType()

const char* ucal_getLocaleByType	(	const UCalendar *	cal,
		ULocDataLocaleType	type,
		UErrorCode *	status
	)

Get the locale for this calendar object.

You can choose between valid and actual locale.

Parameters

cal	The calendar object
type	type of the locale we're looking for (valid or actual)
status	error code for the operation

Returns: the locale name

Stable:: ICU 2.8

◆ ucal_getMillis()

UDate ucal_getMillis	(	const UCalendar *	cal,
		UErrorCode *	status
	)

Get a UCalendar's current time in millis.

The time is represented as milliseconds from the epoch.

Parameters

cal	The UCalendar to query.
status	A pointer to an UErrorCode to receive any errors

Returns: The calendar's current time in millis.

See also: ucal_setMillis; ucal_setDate; ucal_setDateTime

Stable:: ICU 2.0

◆ ucal_getNow()

UDate ucal_getNow ( void )

Get the current date and time.

The value returned is represented as milliseconds from the epoch.

Returns: The current date and time.

Stable:: ICU 2.0

◆ ucal_getTimeZoneDisplayName()

int32_t ucal_getTimeZoneDisplayName	(	const UCalendar *	cal,
		UCalendarDisplayNameType	type,
		const char *	locale,
		UChar *	result,
		int32_t	resultLength,
		UErrorCode *	status
	)

Get the display name for a UCalendar's TimeZone.

A display name is suitable for presentation to a user.

Parameters

cal	The UCalendar to query.
type	The desired display name format; one of UCAL_STANDARD, UCAL_SHORT_STANDARD, UCAL_DST, UCAL_SHORT_DST
locale	The desired locale for the display name.
result	A pointer to a buffer to receive the formatted number.
resultLength	The maximum size of result.
status	A pointer to an UErrorCode to receive any errors

Returns: The total buffer size needed; if greater than resultLength, the output was truncated.

Stable:: ICU 2.0

◆ ucal_getTimeZoneID()

int32_t ucal_getTimeZoneID	(	const UCalendar *	cal,
		UChar *	result,
		int32_t	resultLength,
		UErrorCode *	status
	)

Get the ID of the UCalendar's time zone.

Parameters

cal	The UCalendar to query.
result	Receives the UCalendar's time zone ID.
resultLength	The maximum size of result.
status	Receives the status.

Returns: The total buffer size needed; if greater than resultLength, the output was truncated.

Stable:: ICU 51

◆ ucal_getTimeZoneIDForWindowsID()

int32_t ucal_getTimeZoneIDForWindowsID	(	const UChar *	winid,
		int32_t	len,
		const char *	region,
		UChar *	id,
		int32_t	idCapacity,
		UErrorCode *	status
	)

Converts a Windows time zone ID to an equivalent system time zone ID for a region.

For example, system time zone ID "America/Los_Angeles" is returned for input Windows ID "Pacific Standard Time" and region "US" (or null), "America/Vancouver" is returned for the same Windows ID "Pacific Standard Time" and region "CA".

Not all Windows time zones can be mapped to system time zones. When the input Windows time zone ID is unknown or unmappable to a system time zone, then this function returns 0 as the result length, but the operation itself remains successful (no error status set on return).

This implementation utilizes Zone-Tzid mapping data. The mapping data is updated time to time. To get the latest changes, please read the ICU user guide section Updating the Time Zone Data.

Parameters

winid	A Windows time zone ID.
len	The length of `winid`, or -1 if null-terminated.
region	A null-terminated region code, or `NULL` if no regional preference.
id	A buffer to receive a system time zone ID.
idCapacity	The capacity of the result buffer `id`.
status	Receives the status.

Returns: The result string length, not including the terminating null.

See also: ucal_getWindowsTimeZoneID

Stable:: ICU 52

◆ ucal_getTimeZoneTransitionDate()

UBool ucal_getTimeZoneTransitionDate	(	const UCalendar *	cal,
		UTimeZoneTransitionType	type,
		UDate *	transition,
		UErrorCode *	status
	)

Get the UDate for the next/previous time zone transition relative to the calendar's current date, in the time zone to which the calendar is currently set.

If there is no known time zone transition of the requested type relative to the calendar's date, the function returns FALSE.

Parameters

cal	The UCalendar to query.
type	The type of transition desired.
transition	A pointer to a UDate to be set to the transition time. If the function returns FALSE, the value set is unspecified.
status	A pointer to a UErrorCode to receive any errors.

Returns: TRUE if a valid transition time is set in *transition, FALSE otherwise.

Stable:: ICU 50

◆ ucal_getType()

const char* ucal_getType	(	const UCalendar *	cal,
		UErrorCode *	status
	)

Get the resource keyword value string designating the calendar type for the UCalendar.

Parameters

cal	The UCalendar to query.
status	The error code for the operation.

Returns: The resource keyword value string.

Stable:: ICU 4.2

◆ ucal_getTZDataVersion()

const char* ucal_getTZDataVersion ( UErrorCode * status )

Returns the timezone data version currently used by ICU.

Parameters

status error code for the operation

Returns: the version string, such as "2007f"

Stable:: ICU 3.8

◆ ucal_getWeekendTransition()

int32_t ucal_getWeekendTransition	(	const UCalendar *	cal,
		UCalendarDaysOfWeek	dayOfWeek,
		UErrorCode *	status
	)

Returns the time during the day at which the weekend begins or ends in this calendar system.

If ucal_getDayOfWeekType() returns UCAL_WEEKEND_ONSET for the specified dayOfWeek, return the time at which the weekend begins. If ucal_getDayOfWeekType() returns UCAL_WEEKEND_CEASE for the specified dayOfWeek, return the time at which the weekend ends. If ucal_getDayOfWeekType() returns some other UCalendarWeekdayType for the specified dayOfWeek, is it an error condition (U_ILLEGAL_ARGUMENT_ERROR).

Parameters

cal	The UCalendar to query.
dayOfWeek	The day of the week for which the weekend transition time is desired (UCAL_SUNDAY..UCAL_SATURDAY).
status	The error code for the operation.

Returns: The milliseconds after midnight at which the weekend begins or ends.

Stable:: ICU 4.4

◆ ucal_getWindowsTimeZoneID()

int32_t ucal_getWindowsTimeZoneID	(	const UChar *	id,
		int32_t	len,
		UChar *	winid,
		int32_t	winidCapacity,
		UErrorCode *	status
	)

Converts a system time zone ID to an equivalent Windows time zone ID.

For example, Windows time zone ID "Pacific Standard Time" is returned for input "America/Los_Angeles".

There are system time zones that cannot be mapped to Windows zones. When the input system time zone ID is unknown or unmappable to a Windows time zone, then this function returns 0 as the result length, but the operation itself remains successful (no error status set on return).

This implementation utilizes Zone-Tzid mapping data. The mapping data is updated time to time. To get the latest changes, please read the ICU user guide section Updating the Time Zone Data.

Parameters

id	A system time zone ID.
len	The length of `id`, or -1 if null-terminated.
winid	A buffer to receive a Windows time zone ID.
winidCapacity	The capacity of the result buffer `winid`.
status	Receives the status.

Returns: The result string length, not including the terminating null.

See also: ucal_getTimeZoneIDForWindowsID

Stable:: ICU 52

◆ ucal_inDaylightTime()

UBool ucal_inDaylightTime	(	const UCalendar *	cal,
		UErrorCode *	status
	)

Determine if a UCalendar is currently in daylight savings time.

Daylight savings time is not used in all parts of the world.

Parameters

cal	The UCalendar to query.
status	A pointer to an UErrorCode to receive any errors

Returns: TRUE if cal is currently in daylight savings time, FALSE otherwise

Stable:: ICU 2.0

◆ ucal_isSet()

UBool ucal_isSet	(	const UCalendar *	cal,
		UCalendarDateFields	field
	)

Determine if a field in a UCalendar is set.

All fields are represented as 32-bit integers.

Parameters

cal	The UCalendar to query.
field	The desired field; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.

Returns: TRUE if field is set, FALSE otherwise.

See also: ucal_get; ucal_set; ucal_clearField; ucal_clear

Stable:: ICU 2.0

◆ ucal_isWeekend()

UBool ucal_isWeekend	(	const UCalendar *	cal,
		UDate	date,
		UErrorCode *	status
	)

Returns TRUE if the given UDate is in the weekend in this calendar system.

Parameters

cal	The UCalendar to query.
date	The UDate in question.
status	The error code for the operation.

Returns: TRUE if the given UDate is in the weekend in this calendar system, FALSE otherwise.

Stable:: ICU 4.4

◆ ucal_open()

UCalendar* ucal_open	(	const UChar *	zoneID,
		int32_t	len,
		const char *	locale,
		UCalendarType	type,
		UErrorCode *	status
	)

Open a UCalendar.

A UCalendar may be used to convert a millisecond value to a year, month, and day.

Note: When unknown TimeZone ID is specified or if the TimeZone ID specified is "Etc/Unknown", the UCalendar returned by the function is initialized with GMT zone with TimeZone ID UCAL_UNKNOWN_ZONE_ID ("Etc/Unknown") without any errors/warnings. If you want to check if a TimeZone ID is valid prior to this function, use ucal_getCanonicalTimeZoneID.

Parameters

zoneID	The desired TimeZone ID. If 0, use the default time zone.
len	The length of zoneID, or -1 if null-terminated.
locale	The desired locale
type	The type of UCalendar to open. This can be UCAL_GREGORIAN to open the Gregorian calendar for the locale, or UCAL_DEFAULT to open the default calendar for the locale (the default calendar may also be Gregorian). To open a specific non-Gregorian calendar for the locale, use uloc_setKeywordValue to set the value of the calendar keyword for the locale and then pass the locale to ucal_open with UCAL_DEFAULT as the type.
status	A pointer to an UErrorCode to receive any errors

Returns: A pointer to a UCalendar, or 0 if an error occurred.

See also: UCAL_UNKNOWN_ZONE_ID

Stable:: ICU 2.0

◆ ucal_openCountryTimeZones()

UEnumeration* ucal_openCountryTimeZones	(	const char *	country,
		UErrorCode *	ec
	)

Create an enumeration over all time zones associated with the given country.

Some zones are affiliated with no country (e.g., "UTC"); these may also be retrieved, as a group.

Parameters

country	the ISO 3166 two-letter country code, or NULL to retrieve zones not affiliated with any country
ec	input/output error code

Returns: an enumeration object that the caller must dispose of using uenum_close(), or NULL upon failure. In case of failure *ec will indicate the error.

Stable:: ICU 2.6

◆ ucal_openTimeZoneIDEnumeration()

UEnumeration* ucal_openTimeZoneIDEnumeration	(	USystemTimeZoneType	zoneType,
		const char *	region,
		const int32_t *	rawOffset,
		UErrorCode *	ec
	)

Create an enumeration over system time zone IDs with the given filter conditions.

Parameters

zoneType	The system time zone type.
region	The ISO 3166 two-letter country code or UN M.49 three-digit area code. When NULL, no filtering done by region.
rawOffset	An offset from GMT in milliseconds, ignoring the effect of daylight savings time, if any. When NULL, no filtering done by zone offset.
ec	A pointer to an UErrorCode to receive any errors

Returns: an enumeration object that the caller must dispose of using enum_close(), or NULL upon failure. In case of failure, *ec will indicate the error.

Stable:: ICU 4.8

◆ ucal_openTimeZones()

UEnumeration* ucal_openTimeZones ( UErrorCode * ec )

Create an enumeration over all time zones.

Parameters

ec	input/output error code

Returns: an enumeration object that the caller must dispose of using uenum_close(), or NULL upon failure. In case of failure *ec will indicate the error.

Stable:: ICU 2.6

◆ ucal_roll()

void ucal_roll	(	UCalendar *	cal,
		UCalendarDateFields	field,
		int32_t	amount,
		UErrorCode *	status
	)

Add a specified signed amount to a particular field in a UCalendar.

This will not modify more significant fields in the calendar. Rolling by a positive value always means moving forward in time (unless the limit of the field is reached, in which case it may pin or wrap), so for Gregorian calendar, starting with 100 BC and rolling the year by +1 results in 99 BC. When eras have a definite beginning and end (as in the Chinese calendar, or as in most eras in the Japanese calendar) then rolling the year past either limit of the era will cause the year to wrap around. When eras only have a limit at one end, then attempting to roll the year past that limit will result in pinning the year at that limit. Note that for most calendars in which era 0 years move forward in time (such as Buddhist, Hebrew, or Islamic), it is possible for add or roll to result in negative years for era 0 (that is the only way to represent years before the calendar epoch).

Parameters

cal	The UCalendar to which to add.
field	The field to which to add the signed value; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
amount	The signed amount to add to field. If the amount causes the value to exceed to maximum or minimum values for that field, the field is pinned to a permissible value.
status	A pointer to an UErrorCode to receive any errors

See also: ucal_add

Stable:: ICU 2.0

◆ ucal_set()

void ucal_set	(	UCalendar *	cal,
		UCalendarDateFields	field,
		int32_t	value
	)

Set the value of a field in a UCalendar.

All fields are represented as 32-bit integers.

Parameters

cal	The UCalendar to set.
field	The field to set; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH, UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK, UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND, UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
value	The desired value of field.

See also: ucal_get; ucal_isSet; ucal_clearField; ucal_clear

Stable:: ICU 2.0

◆ ucal_setAttribute()

void ucal_setAttribute	(	UCalendar *	cal,
		UCalendarAttribute	attr,
		int32_t	newValue
	)

Set a numeric attribute associated with a UCalendar.

Numeric attributes include the first day of the week, or the minimal numbers of days in the first week of the month.

Parameters

cal	The UCalendar to set.
attr	The desired attribute; one of UCAL_LENIENT, UCAL_FIRST_DAY_OF_WEEK, UCAL_MINIMAL_DAYS_IN_FIRST_WEEK, UCAL_REPEATED_WALL_TIME or UCAL_SKIPPED_WALL_TIME
newValue	The new value of attr.

See also: ucal_getAttribute

Stable:: ICU 2.0

◆ ucal_setDate()

void ucal_setDate	(	UCalendar *	cal,
		int32_t	year,
		int32_t	month,
		int32_t	date,
		UErrorCode *	status
	)

Set a UCalendar's current date.

The date is represented as a series of 32-bit integers.

Parameters

cal	The UCalendar to set.
year	The desired year.
month	The desired month; one of UCAL_JANUARY, UCAL_FEBRUARY, UCAL_MARCH, UCAL_APRIL, UCAL_MAY, UCAL_JUNE, UCAL_JULY, UCAL_AUGUST, UCAL_SEPTEMBER, UCAL_OCTOBER, UCAL_NOVEMBER, UCAL_DECEMBER, UCAL_UNDECIMBER
date	The desired day of the month.
status	A pointer to an UErrorCode to receive any errors

See also: ucal_getMillis; ucal_setMillis; ucal_setDateTime

Stable:: ICU 2.0

◆ ucal_setDateTime()

void ucal_setDateTime	(	UCalendar *	cal,
		int32_t	year,
		int32_t	month,
		int32_t	date,
		int32_t	hour,
		int32_t	minute,
		int32_t	second,
		UErrorCode *	status
	)

Set a UCalendar's current date.

The date is represented as a series of 32-bit integers.

Parameters

cal	The UCalendar to set.
year	The desired year.
month	The desired month; one of UCAL_JANUARY, UCAL_FEBRUARY, UCAL_MARCH, UCAL_APRIL, UCAL_MAY, UCAL_JUNE, UCAL_JULY, UCAL_AUGUST, UCAL_SEPTEMBER, UCAL_OCTOBER, UCAL_NOVEMBER, UCAL_DECEMBER, UCAL_UNDECIMBER
date	The desired day of the month.
hour	The desired hour of day.
minute	The desired minute.
second	The desirec second.
status	A pointer to an UErrorCode to receive any errors

See also: ucal_getMillis; ucal_setMillis; ucal_setDate

Stable:: ICU 2.0

◆ ucal_setDefaultTimeZone()

void ucal_setDefaultTimeZone	(	const UChar *	zoneID,
		UErrorCode *	ec
	)

Set the default time zone.

Parameters

zoneID	null-terminated time zone ID
ec	input/output error code

Stable:: ICU 2.6

◆ ucal_setGregorianChange()

void ucal_setGregorianChange	(	UCalendar *	cal,
		UDate	date,
		UErrorCode *	pErrorCode
	)

Sets the GregorianCalendar change date.

This is the point when the switch from Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October 15, 1582. Previous to this time and date will be Julian dates.

This function works only for Gregorian calendars. If the UCalendar is not an instance of a Gregorian calendar, then a U_UNSUPPORTED_ERROR error code is set.

Parameters

cal	The calendar object.
date	The given Gregorian cutover date.
pErrorCode	Pointer to a standard ICU error code. Its input value must pass the U_SUCCESS() test, or else the function returns immediately. Check for U_FAILURE() on output or use with function chaining. (See User Guide for details.)

See also: GregorianCalendar::setGregorianChange; ucal_getGregorianChange

Stable:: ICU 3.6

◆ ucal_setMillis()

void ucal_setMillis	(	UCalendar *	cal,
		UDate	dateTime,
		UErrorCode *	status
	)

Set a UCalendar's current time in millis.

The time is represented as milliseconds from the epoch.

Parameters

cal	The UCalendar to set.
dateTime	The desired date and time.
status	A pointer to an UErrorCode to receive any errors

See also: ucal_getMillis; ucal_setDate; ucal_setDateTime

Stable:: ICU 2.0

◆ ucal_setTimeZone()

void ucal_setTimeZone	(	UCalendar *	cal,
		const UChar *	zoneID,
		int32_t	len,
		UErrorCode *	status
	)

Set the TimeZone used by a UCalendar.

A UCalendar uses a timezone for converting from Greenwich time to local time.

Parameters

cal	The UCalendar to set.
zoneID	The desired TimeZone ID. If 0, use the default time zone.
len	The length of zoneID, or -1 if null-terminated.
status	A pointer to an UErrorCode to receive any errors.

Stable:: ICU 2.0

Namespaces

Macros

Typedefs

Enumerations

Functions

Detailed Description

Calendar C API

Macro Definition Documentation

◆ UCAL_UNKNOWN_ZONE_ID

Typedef Documentation

◆ UCalendar

◆ UCalendarAMPMs

◆ UCalendarAttribute

◆ UCalendarDateFields

◆ UCalendarDaysOfWeek

◆ UCalendarDisplayNameType

◆ UCalendarLimitType

◆ UCalendarMonths

◆ UCalendarType

◆ UCalendarWallTimeOption

◆ UCalendarWeekdayType

◆ USystemTimeZoneType

◆ UTimeZoneTransitionType

Enumeration Type Documentation

◆ UCalendarAMPMs

◆ UCalendarAttribute

◆ UCalendarDateFields

◆ UCalendarDaysOfWeek

◆ UCalendarDisplayNameType

◆ UCalendarLimitType

◆ UCalendarMonths

◆ UCalendarType

◆ UCalendarWallTimeOption

◆ UCalendarWeekdayType

◆ USystemTimeZoneType

◆ UTimeZoneTransitionType

Function Documentation

◆ ucal_add()

◆ ucal_clear()

◆ ucal_clearField()

◆ ucal_clone()

◆ ucal_close()

◆ ucal_countAvailable()

◆ ucal_equivalentTo()

◆ ucal_get()

◆ ucal_getAttribute()

◆ ucal_getAvailable()

◆ ucal_getCanonicalTimeZoneID()

◆ ucal_getDayOfWeekType()

◆ ucal_getDefaultTimeZone()

◆ ucal_getDSTSavings()

◆ ucal_getFieldDifference()

◆ ucal_getGregorianChange()

◆ ucal_getHostTimeZone()

◆ ucal_getKeywordValuesForLocale()

◆ ucal_getLimit()

◆ ucal_getLocaleByType()

◆ ucal_getMillis()

◆ ucal_getNow()

◆ ucal_getTimeZoneDisplayName()

◆ ucal_getTimeZoneID()

◆ ucal_getTimeZoneIDForWindowsID()

◆ ucal_getTimeZoneTransitionDate()

◆ ucal_getType()

◆ ucal_getTZDataVersion()

◆ ucal_getWeekendTransition()

◆ ucal_getWindowsTimeZoneID()

◆ ucal_inDaylightTime()

◆ ucal_isSet()

◆ ucal_isWeekend()

◆ ucal_open()

◆ ucal_openCountryTimeZones()

◆ ucal_openTimeZoneIDEnumeration()

◆ ucal_openTimeZones()

◆ ucal_roll()

◆ ucal_set()

◆ ucal_setAttribute()

◆ ucal_setDate()

◆ ucal_setDateTime()

◆ ucal_setDefaultTimeZone()