<GDateTime>

<GDateTime>

Description

An opaque structure that represents a date and time, including a time zone.

Functions

add

(define-values (%return) (date-time:add self timespan))

Creates a copy of datetime and adds the specified timespan to the copy.

Parameters

datetime

a GDateTime

Passed as self

timespan

a GTimeSpan

Passed as timespan

add-days

(define-values (%return) (date-time:add-days self days))

Creates a copy of datetime and adds the specified number of days to the copy. Add negative values to subtract days.

Parameters

datetime

a GDateTime

Passed as self

days

the number of days

Passed as days

add-full

(define-values
  (%return)
  (date-time:add-full self years months days hours minutes seconds))

Creates a new GDateTime adding the specified values to the current date and time in datetime. Add negative values to subtract.

Parameters

datetime

a GDateTime

Passed as self

years

the number of years to add

Passed as years

months

the number of months to add

Passed as months

days

the number of days to add

Passed as days

hours

the number of hours to add

Passed as hours

minutes

the number of minutes to add

Passed as minutes

seconds

the number of seconds to add

Passed as seconds

add-hours

(define-values (%return) (date-time:add-hours self hours))

Creates a copy of datetime and adds the specified number of hours. Add negative values to subtract hours.

Parameters

datetime

a GDateTime

Passed as self

hours

the number of hours to add

Passed as hours

add-minutes

(define-values (%return) (date-time:add-minutes self minutes))

Creates a copy of datetime adding the specified number of minutes. Add negative values to subtract minutes.

Parameters

datetime

a GDateTime

Passed as self

minutes

the number of minutes to add

Passed as minutes

add-months

(define-values (%return) (date-time:add-months self months))

Creates a copy of datetime and adds the specified number of months to the copy. Add negative values to subtract months.

The day of the month of the resulting GDateTime is clamped to the number of days in the updated calendar month. For example, if adding 1 month to 31st January 2018, the result would be 28th February 2018. In 2020 (a leap year), the result would be 29th February.

Parameters

datetime

a GDateTime

Passed as self

months

the number of months

Passed as months

add-seconds

(define-values (%return) (date-time:add-seconds self seconds))

Creates a copy of datetime and adds the specified number of seconds. Add negative values to subtract seconds.

Parameters

datetime

a GDateTime

Passed as self

seconds

the number of seconds to add

Passed as seconds

add-weeks

(define-values (%return) (date-time:add-weeks self weeks))

Creates a copy of datetime and adds the specified number of weeks to the copy. Add negative values to subtract weeks.

Parameters

datetime

a GDateTime

Passed as self

weeks

the number of weeks

Passed as weeks

add-years

(define-values (%return) (date-time:add-years self years))

Creates a copy of datetime and adds the specified number of years to the copy. Add negative values to subtract years.

As with g_date_time_add_months(), if the resulting date would be 29th February on a non-leap year, the day will be clamped to 28th February.

Parameters

datetime

a GDateTime

Passed as self

years

the number of years

Passed as years

difference

(define-values (%return) (date-time:difference self begin))

Calculates the difference in time between end and begin. The GTimeSpan that is returned is effectively end - begin (ie: positive if the first parameter is larger).

Parameters

end

a GDateTime

Passed as self

begin

a GDateTime

Passed as begin

format

(define-values (%return) (date-time:format self format))

Creates a newly allocated string representing the requested format.

The format strings understood by this function are a subset of the strftime() format language as specified by C99. The \%D, \%U and \%W conversions are not supported, nor is the 'E' modifier. The GNU extensions \%k, \%l, \%s and \%P are supported, however, as are the '0', '_' and '-' modifiers. The Python extension \%f is also supported.

In contrast to strftime(), this function always produces a UTF-8 string, regardless of the current locale. Note that the rendering of many formats is locale-dependent and may not match the strftime() output exactly.

The following format specifiers are supported:

- \%a: the abbreviated weekday name according to the current locale - \%A: the full weekday name according to the current locale - \%b: the abbreviated month name according to the current locale - \%B: the full month name according to the current locale - \%c: the preferred date and time representation for the current locale - \%C: the century number (year/100) as a 2-digit integer (00-99) - \%d: the day of the month as a decimal number (range 01 to 31) - \%e: the day of the month as a decimal number (range 1 to 31) - \%F: equivalent to %Y-%m-%d (the ISO 8601 date format) - \%g: the last two digits of the ISO 8601 week-based year as a decimal number (00-99). This works well with \%V and \%u. - \%G: the ISO 8601 week-based year as a decimal number. This works well with \%V and \%u. - \%h: equivalent to \%b - \%H: the hour as a decimal number using a 24-hour clock (range 00 to 23) - \%I: the hour as a decimal number using a 12-hour clock (range 01 to 12) - \%j: the day of the year as a decimal number (range 001 to 366) - \%k: the hour (24-hour clock) as a decimal number (range 0 to 23); single digits are preceded by a blank - \%l: the hour (12-hour clock) as a decimal number (range 1 to 12); single digits are preceded by a blank - \%m: the month as a decimal number (range 01 to 12) - \%M: the minute as a decimal number (range 00 to 59) - \%f: the microsecond as a decimal number (range 000000 to 999999) - \%p: either "AM" or "PM" according to the given time value, or the corresponding strings for the current locale. Noon is treated as "PM" and midnight as "AM". Use of this format specifier is discouraged, as many locales have no concept of AM/PM formatting. Use \%c or \%X instead. - \%P: like \%p but lowercase: "am" or "pm" or a corresponding string for the current locale. Use of this format specifier is discouraged, as many locales have no concept of AM/PM formatting. Use \%c or \%X instead. - \%r: the time in a.m. or p.m. notation. Use of this format specifier is discouraged, as many locales have no concept of AM/PM formatting. Use \%c or \%X instead. - \%R: the time in 24-hour notation (\%H:\%M) - \%s: the number of seconds since the Epoch, that is, since 1970-01-01 00:00:00 UTC - \%S: the second as a decimal number (range 00 to 60) - \%t: a tab character - \%T: the time in 24-hour notation with seconds (\%H:\%M:\%S) - \%u: the ISO 8601 standard day of the week as a decimal, range 1 to 7, Monday being 1. This works well with \%G and \%V. - \%V: the ISO 8601 standard week number of the current year as a decimal number, range 01 to 53, where week 1 is the first week that has at least 4 days in the new year. See g_date_time_get_week_of_year(). This works well with \%G and \%u. - \%w: the day of the week as a decimal, range 0 to 6, Sunday being 0. This is not the ISO 8601 standard format -- use \%u instead. - \%x: the preferred date representation for the current locale without the time - \%X: the preferred time representation for the current locale without the date - \%y: the year as a decimal number without the century - \%Y: the year as a decimal number including the century - \%z: the time zone as an offset from UTC (+hhmm) - \%:z: the time zone as an offset from UTC (+hh:mm). This is a gnulib strftime() extension. Since: 2.38 - \%::z: the time zone as an offset from UTC (+hh:mm:ss). This is a gnulib strftime() extension. Since: 2.38 - \%:::z: the time zone as an offset from UTC, with : to necessary precision (e.g., -04, +05:30). This is a gnulib strftime() extension. Since: 2.38 - \%Z: the time zone or name or abbreviation - \%\%: a literal \% character

Some conversion specifications can be modified by preceding the conversion specifier by one or more modifier characters. The following modifiers are supported for many of the numeric conversions:

- O: Use alternative numeric symbols, if the current locale supports those. - _: Pad a numeric result with spaces. This overrides the default padding for the specifier. - -: Do not pad a numeric result. This overrides the default padding for the specifier. - 0: Pad a numeric result with zeros. This overrides the default padding for the specifier.

Additionally, when O is used with B, b, or h, it produces the alternative form of a month name. The alternative form should be used when the month name is used without a day number (e.g., standalone). It is required in some languages (Baltic, Slavic, Greek, and more) due to their grammatical rules. For other languages there is no difference. \%OB is a GNU and BSD strftime() extension expected to be added to the future POSIX specification, \%Ob and \%Oh are GNU strftime() extensions. Since: 2.56

Parameters

datetime

A GDateTime

Passed as self

format

a valid UTF-8 string, containing the format for the GDateTime

Passed as format

format-iso8601

(define-values (%return) (date-time:format-iso8601 self))

Format datetime in [ISO 8601 format](https://en.wikipedia.org/wiki/ISO_8601), including the date, time and time zone, and return that as a UTF-8 encoded string.

Since GLib 2.66, this will output to sub-second precision if needed.

Parameters

datetime

A GDateTime

Passed as self

get-day-of-month

(define-values (%return) (date-time:get-day-of-month self))

Retrieves the day of the month represented by datetime in the gregorian calendar.

Parameters

datetime

a GDateTime

Passed as self

get-day-of-week

(define-values (%return) (date-time:get-day-of-week self))

Retrieves the ISO 8601 day of the week on which datetime falls (1 is Monday, 2 is Tuesday... 7 is Sunday).

Parameters

datetime

a GDateTime

Passed as self

get-day-of-year

(define-values (%return) (date-time:get-day-of-year self))

Retrieves the day of the year represented by datetime in the Gregorian calendar.

Parameters

datetime

a GDateTime

Passed as self

get-hour

(define-values (%return) (date-time:get-hour self))

Retrieves the hour of the day represented by datetime

Parameters

datetime

a GDateTime

Passed as self

get-microsecond

(define-values (%return) (date-time:get-microsecond self))

Retrieves the microsecond of the date represented by datetime

Parameters

datetime

a GDateTime

Passed as self

get-minute

(define-values (%return) (date-time:get-minute self))

Retrieves the minute of the hour represented by datetime

Parameters

datetime

a GDateTime

Passed as self

get-month

(define-values (%return) (date-time:get-month self))

Retrieves the month of the year represented by datetime in the Gregorian calendar.

Parameters

datetime

a GDateTime

Passed as self

get-second

(define-values (%return) (date-time:get-second self))

Retrieves the second of the minute represented by datetime

Parameters

datetime

a GDateTime

Passed as self

get-seconds

(define-values (%return) (date-time:get-seconds self))

Retrieves the number of seconds since the start of the last minute, including the fractional part.

Parameters

datetime

a GDateTime

Passed as self

get-timezone

(define-values (%return) (date-time:get-timezone self))

Get the time zone for this datetime.

Parameters

datetime

a GDateTime

Passed as self

get-timezone-abbreviation

(define-values (%return) (date-time:get-timezone-abbreviation self))

Determines the time zone abbreviation to be used at the time and in the time zone of datetime.

For example, in Toronto this is currently "EST" during the winter months and "EDT" during the summer months when daylight savings time is in effect.

Parameters

datetime

a GDateTime

Passed as self

get-utc-offset

(define-values (%return) (date-time:get-utc-offset self))

Determines the offset to UTC in effect at the time and in the time zone of datetime.

The offset is the number of microseconds that you add to UTC time to arrive at local time for the time zone (ie: negative numbers for time zones west of GMT, positive numbers for east).

If datetime represents UTC time, then the offset is always zero.

Parameters

datetime

a GDateTime

Passed as self

get-week-numbering-year

(define-values (%return) (date-time:get-week-numbering-year self))

Returns the ISO 8601 week-numbering year in which the week containing datetime falls.

This function, taken together with g_date_time_get_week_of_year() and g_date_time_get_day_of_week() can be used to determine the full ISO week date on which datetime falls.

This is usually equal to the normal Gregorian year (as returned by g_date_time_get_year()), except as detailed below:

For Thursday, the week-numbering year is always equal to the usual calendar year. For other days, the number is such that every day within a complete week (Monday to Sunday) is contained within the same week-numbering year.

For Monday, Tuesday and Wednesday occurring near the end of the year, this may mean that the week-numbering year is one greater than the calendar year (so that these days have the same week-numbering year as the Thursday occurring early in the next year).

For Friday, Saturday and Sunday occurring near the start of the year, this may mean that the week-numbering year is one less than the calendar year (so that these days have the same week-numbering year as the Thursday occurring late in the previous year).

An equivalent description is that the week-numbering year is equal to the calendar year containing the majority of the days in the current week (Monday to Sunday).

Note that January 1 0001 in the proleptic Gregorian calendar is a Monday, so this function never returns 0.

Parameters

datetime

a GDateTime

Passed as self

get-week-of-year

(define-values (%return) (date-time:get-week-of-year self))

Returns the ISO 8601 week number for the week containing datetime. The ISO 8601 week number is the same for every day of the week (from Moday through Sunday). That can produce some unusual results (described below).

The first week of the year is week 1. This is the week that contains the first Thursday of the year. Equivalently, this is the first week that has more than 4 of its days falling within the calendar year.

The value 0 is never returned by this function. Days contained within a year but occurring before the first ISO 8601 week of that year are considered as being contained in the last week of the previous year. Similarly, the final days of a calendar year may be considered as being part of the first ISO 8601 week of the next year if 4 or more days of that week are contained within the new year.

Parameters

datetime

a GDateTime

Passed as self

get-year

(define-values (%return) (date-time:get-year self))

Retrieves the year represented by datetime in the Gregorian calendar.

Parameters

datetime

A GDateTime

Passed as self

get-ymd

(define-values (year month day) (date-time:get-ymd self))

Retrieves the Gregorian day, month, and year of a given GDateTime.

Parameters

datetime

a GDateTime.

Passed as self

year

the return location for the gregorian year, or NULL.

Passed as year

month

the return location for the month of the year, or NULL.

Passed as month

day

the return location for the day of the month, or NULL.

Passed as day

is-daylight-savings?

(define-values (%return) (date-time:is-daylight-savings? self))

Determines if daylight savings time is in effect at the time and in the time zone of datetime.

Parameters

datetime

a GDateTime

Passed as self

ref

(define-values (%return) (date-time:ref self))

Atomically increments the reference count of datetime by one.

Parameters

datetime

a GDateTime

Passed as self

to-local

(define-values (%return) (date-time:to-local self))

Creates a new GDateTime corresponding to the same instant in time as datetime, but in the local time zone.

This call is equivalent to calling g_date_time_to_timezone() with the time zone returned by g_time_zone_new_local().

Parameters

datetime

a GDateTime

Passed as self

to-timezone

(define-values (%return) (date-time:to-timezone self tz))

Create a new GDateTime corresponding to the same instant in time as datetime, but in the time zone tz.

This call can fail in the case that the time goes out of bounds. For example, converting 0001-01-01 00:00:00 UTC to a time zone west of Greenwich will fail (due to the year 0 being out of range).

Parameters

datetime

a GDateTime

Passed as self

tz

the new GTimeZone

Passed as tz

to-unix

(define-values (%return) (date-time:to-unix self))

Gives the Unix time corresponding to datetime, rounding down to the nearest second.

Unix time is the number of seconds that have elapsed since 1970-01-01 00:00:00 UTC, regardless of the time zone associated with datetime.

Parameters

datetime

a GDateTime

Passed as self

to-utc

(define-values (%return) (date-time:to-utc self))

Creates a new GDateTime corresponding to the same instant in time as datetime, but in UTC.

This call is equivalent to calling g_date_time_to_timezone() with the time zone returned by g_time_zone_new_utc().

Parameters

datetime

a GDateTime

Passed as self

unref

(define-values () (date-time:unref self))

Atomically decrements the reference count of datetime by one.

When the reference count reaches zero, the resources allocated by datetime are freed

Parameters

datetime

a GDateTime

Passed as self

date-time:new-utc

(define-values
  (%return)
  (date-time:new-utc year month day hour minute seconds))

Undocumented

Parameters

year

Passed as year

month

Passed as month

day

Passed as day

hour

Passed as hour

minute

Passed as minute

seconds

Passed as seconds

date-time:new-now-utc

(define-values (%return) (date-time:new-now-utc))

Undocumented

date-time:new-now-local

(define-values (%return) (date-time:new-now-local))

Undocumented

date-time:new-now

(define-values (%return) (date-time:new-now tz))

Undocumented

Parameters

tz

Passed as tz

date-time:new-local

(define-values
  (%return)
  (date-time:new-local year month day hour minute seconds))

Undocumented

Parameters

year

Passed as year

month

Passed as month

day

Passed as day

hour

Passed as hour

minute

Passed as minute

seconds

Passed as seconds

date-time:new-from-unix-utc

(define-values (%return) (date-time:new-from-unix-utc t))

Undocumented

Parameters

t

Passed as t

date-time:new-from-unix-local

(define-values (%return) (date-time:new-from-unix-local t))

Undocumented

Parameters

t

Passed as t

date-time:new-from-iso8601

(define-values (%return) (date-time:new-from-iso8601 text default-tz))

Undocumented

Parameters

text

Passed as text

default_tz

Passed as default-tz

date-time:new

(define-values
  (%return)
  (date-time:new tz year month day hour minute seconds))

Undocumented

Parameters

tz

Passed as tz

year

Passed as year

month

Passed as month

day

Passed as day

hour

Passed as hour

minute

Passed as minute

seconds

Passed as seconds

date-time:compare

(define-values (%return) (date-time:compare dt1 dt2))

A comparison function for GDateTimes that is suitable as a GCompareFunc. Both GDateTimes must be non-NULL.

Parameters

dt1

first GDateTime to compare

Passed as dt1

dt2

second GDateTime to compare

Passed as dt2

date-time:equal?

(define-values (%return) (date-time:equal? dt1 dt2))

Checks to see if dt1 and dt2 are equal.

Equal here means that they represent the same moment after converting them to the same time zone.

Parameters

dt1

a GDateTime

Passed as dt1

dt2

a GDateTime

Passed as dt2

date-time:hash

(define-values (%return) (date-time:hash datetime))

Hashes datetime into a guint, suitable for use within GHashTable.

Parameters

datetime

a GDateTime

Passed as datetime