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Return the number of seconds since 1970-01-01 00:00:00 UTC, excluding leap seconds.
Return a pair containing the number of seconds and microseconds since 1970-01-01 00:00:00 UTC, excluding leap seconds. Note: whether true microsecond resolution is available depends on the operating system.
The following procedures either accept an object representing a broken down time and return a selected component, or accept an object representing a broken down time and a value and set the component to the value. The numbers in parentheses give the usual range.
Seconds (0-59).
Minutes (0-59).
Hours (0-23).
Day of the month (1-31).
Month (0-11).
Year (70-), the year minus 1900.
Day of the week (0-6) with Sunday represented as 0.
Day of the year (0-364, 365 in leap years).
Daylight saving indicator (0 for “no”, greater than 0 for “yes”, less than 0 for “unknown”).
Time zone offset in seconds west of UTC (-46800 to 43200). For example on East coast USA (zone ‘EST+5’) this would be 18000 (ie. 5*60*60) in winter, or 14400 (ie. 4*60*60) during daylight savings.
Note tm:gmtoff
is not the same as tm_gmtoff
in the C
tm
structure. tm_gmtoff
is seconds east and hence the
negative of the value here.
Time zone label (a string), not necessarily unique.
Return an object representing the broken down components of
time, an integer like the one returned by
current-time
. The time zone for the calculation is
optionally specified by zone (a string), otherwise the
TZ
environment variable or the system default is used.
Return an object representing the broken down components of
time, an integer like the one returned by
current-time
. The values are calculated for UTC.
For a broken down time object sbd-time, return a pair the
car
of which is an integer time like current-time
, and
the cdr
of which is a new broken down time with normalized
fields.
zone is a timezone string, or the default is the TZ
environment variable or the system default (see Specifying the Time Zone with TZ
in GNU C Library Reference
Manual). sbd-time is taken to be in that zone.
The following fields of sbd-time are used: tm:year
,
tm:mon
, tm:mday
, tm:hour
, tm:min
,
tm:sec
, tm:isdst
. The values can be outside their usual
ranges. For example tm:hour
normally goes up to 23, but a
value say 33 would mean 9 the following day.
tm:isdst
in sbd-time says whether the time given is with
daylight savings or not. This is ignored if zone doesn’t have
any daylight savings adjustment amount.
The broken down time in the return normalizes the values of
sbd-time by bringing them into their usual ranges, and using the
actual daylight savings rule for that time in zone (which may
differ from what sbd-time had). The easiest way to think of
this is that sbd-time plus zone converts to the integer
UTC time, then a localtime
is applied to get the normal
presentation of that time, in zone.
Initialize the timezone from the TZ
environment variable
or the system default. It’s not usually necessary to call this procedure
since it’s done automatically by other procedures that depend on the
timezone.
Return a string which is broken-down time structure tm formatted according to the given format string.
format contains field specifications introduced by a ‘%’ character. See Formatting Calendar Time in The GNU C Library Reference Manual, or ‘man 3 strftime’, for the available formatting.
(strftime "%c" (localtime (current-time))) ⇒ "Mon Mar 11 20:17:43 2002"
If setlocale
has been called (see Locales), month and day
names are from the current locale and in the locale character set.
Performs the reverse action to strftime
, parsing
string according to the specification supplied in
format. The interpretation of month and day names is
dependent on the current locale. The value returned is a pair.
The CAR has an object with time components
in the form returned by localtime
or gmtime
,
but the time zone components
are not usefully set.
The CDR reports the number of characters from string
which were used for the conversion.
The value of this variable is the number of time units per second reported by the following procedures.
Return an object with information about real and processor time. The following procedures accept such an object as an argument and return a selected component:
The current real time, expressed as time units relative to an arbitrary base.
The CPU time units used by the calling process.
The CPU time units used by the system on behalf of the calling process.
The CPU time units used by terminated child processes of the
calling process, whose status has been collected (e.g., using
waitpid
).
Similarly, the CPU times units used by the system on behalf of terminated child processes.
Return the number of time units since the interpreter was started.
Return the number of time units of processor time used by the interpreter. Both system and user time are included but subprocesses are not.
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