PARSEDATE(3) BSD Library Functions Manual PARSEDATE(3)
parsedate -- date parsing function
System Utilities Library (libutil, -lutil)
parsedate(const char *datestr, const time_t *time, const int *tzoff);
The parsedate() function parses a datetime from datestr described in english relative to an
optional time point and an optional timezone offset in seconds specified in tzoff. If
either time or tzoff are NULL, then the current time and timezone offset are used.
The datestr is a sequence of white-space separated items. The white-space is optional the
concatenated items are not ambiguous. An empty datestr is equivalent to midnight today (the
beginning of this day).
The following words have the indicated numeric meanings: last = -1, this = 0, first, next,
or one = 1, second is unused so that it is not confused with ``seconds'', two = 2, third or
three = 3, fourth or four = 4, fifth or five = 5, sixth or six = 6, seventh or seven = 7,
eighth or eight = 8, ninth or nine = 9, tenth or ten = 10, eleventh or eleven = 11, twelfth
or twoelve = 12.
The following words are recognized in English only: AM, PM, a.m., p.m.
The months: january, february, march, april, may, june, july, august, september, sept,
october, november, december,
The days of the week: sunday, monday, tuesday, tues, wednesday, wednes, thursday, thur,
thurs, friday, saturday.
Time units: year, month, fortnight, week, day, hour, minute, min, second, sec, tomorrow,
Timezone names: gmt, ut, utc, wet, bst, wat, at, ast, adt, est, edt, cst, cdt, mst, mdt,
pst, pdt, yst, ydt, hst, hdt, cat, ahst, nt, idlw, cet, met, mewt, mest, swt, sst, fwt, fst,
eet, bt, zp4, zp5, zp6, wast, wadt, cct, jst, east, eadt, gst, nzt, nzst, nzdt, idle.
A variety of unambiguous dates are recognized:
69-09-10 For years between 69-99 we assume 1900+ and for years between 0-68 we assume
2006-11-17 An ISO-8601 date.
10/1/2000 October 10, 2000; the common US format.
20 Jun 1994
1-sep-06 Other common abbreviations.
1/11 the year can be omitted
As well as times:
Relative items are also supported:
one week ago
Seconds since epoch (also known as UNIX time) are also supported:
@735275209 Tue Apr 20 03:06:49 UTC 1993
parsedate() returns the number of seconds passed since the Epoch, or -1 if the date could
not be parsed properly.
The parser used in parsedate() was originally written by Steven M. Bellovin while at the
University of North Carolina at Chapel Hill. It was later tweaked by a couple of people on
Usenet. Completely overhauled by Rich $alz and Jim Berets in August, 1990.
The parsedate() function first appeared in NetBSD 4.0.
The parsedate() function is not re-entrant or thread-safe.
The parsedate() function cannot compute days before the unix epoch (19700101).
The parsedate() function assumes years less than 0 mean - year, years less than 70 mean
2000 + year, years less than 100 mean 1900 + year.
BSD December 20, 2010 BSD