xref: /netbsd-src/lib/libutil/parsedate.3 (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1.\"     $NetBSD: parsedate.3,v 1.4 2008/04/30 13:10:52 martin Exp $
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30.Dd November 17, 2006
31.Dt PARSEDATE 3
32.Os
33.Sh NAME
34.Nm parsedate
35.Nd date parsing function
36.Sh LIBRARY
37.Lb libutil
38.Sh SYNOPSIS
39.In util.h
40.Ft time_t
41.Fn parsedate "const char *datestr" "const time_t *time" "const int *tzoff"
42.Sh DESCRIPTION
43The
44.Nm parsedate
45function parses a datetime from
46.Ar datestr
47described in english relative to an optional
48.Ar time
49point and an optional timezone offset in seconds specified in
50.Ar tzoff .
51If either
52.Ar time
53or
54.Ar tzoff
55are
56.Dv NULL ,
57then the current time and timezone offset are used.
58.Pp
59The
60.Ar datestr
61is a sequence of white-space separated items.
62The white-space is optional the concatenated items are not ambiguous.
63An empty
64.Ar datestr
65is equivalent to midnight today (the beginning of this day).
66.Pp
67The following words have the indicated numeric meanings:
68.Dv last =
69\-1,
70.Dv this =
710,
72.Dv first or next
731,
74.Dv second
75is unused so that it is not confused with
76.Dq seconds ,
77.Dv third =
783,
79.Dv fourth =
804,
81.Dv fifth =
825,
83.Dv sixth =
846,
85.Dv seventh =
867,
87.Dv eighth =
888,
89.Dv ninth =
909,
91.Dv tenth =
9210,
93.Dv eleventh =
9411,
95.Dv twelfth =
9612.
97.Pp
98The following words are recognized in English only:
99.Dv AM ,
100.Dv PM ,
101.Dv a.m. ,
102.Dv p.m.
103.Pp
104The months:
105.Dv january ,
106.Dv february ,
107.Dv march ,
108.Dv april ,
109.Dv may ,
110.Dv june ,
111.Dv july ,
112.Dv august ,
113.Dv september ,
114.Dv sept ,
115.Dv october ,
116.Dv november ,
117.Dv december ,
118.Pp
119The days of the week:
120.Dv sunday ,
121.Dv monday ,
122.Dv tuesday ,
123.Dv tues ,
124.Dv wednesday ,
125.Dv wednes ,
126.Dv thursday ,
127.Dv thur ,
128.Dv thurs ,
129.Dv friday ,
130.Dv saturday .
131.Pp
132Time units:
133.Dv year ,
134.Dv month ,
135.Dv fortnight ,
136.Dv week ,
137.Dv day ,
138.Dv hour ,
139.Dv minute ,
140.Dv min ,
141.Dv second ,
142.Dv sec ,
143.Dv tomorrow ,
144.Dv yesterday .
145.Pp
146Timezone names:
147.Dv gmt ,
148.Dv ut ,
149.Dv utc ,
150.Dv wet ,
151.Dv bst ,
152.Dv wat ,
153.Dv at ,
154.Dv ast ,
155.Dv adt ,
156.Dv est ,
157.Dv edt ,
158.Dv cst ,
159.Dv cdt ,
160.Dv mst ,
161.Dv mdt ,
162.Dv pst ,
163.Dv pdt ,
164.Dv yst ,
165.Dv ydt ,
166.Dv hst ,
167.Dv hdt ,
168.Dv cat ,
169.Dv ahst ,
170.Dv nt ,
171.Dv idlw ,
172.Dv cet ,
173.Dv met ,
174.Dv mewt ,
175.Dv mest ,
176.Dv swt ,
177.Dv sst ,
178.Dv fwt ,
179.Dv fst ,
180.Dv eet ,
181.Dv bt ,
182.Dv zp4 ,
183.Dv zp5 ,
184.Dv zp6 ,
185.Dv wast ,
186.Dv wadt ,
187.Dv cct ,
188.Dv jst ,
189.Dv east ,
190.Dv eadt ,
191.Dv gst ,
192.Dv nzt ,
193.Dv nzst ,
194.Dv nzdt ,
195.Dv idle .
196.Pp
197A variety of unambiguous dates are recognized:
198.Bl -tag -compact
199.It 69-09-10
200For years between 69-99 we assume 1900+ and for years between 0-68
201we assume 2000+.
202.It 2006-11-17
203An ISO-8601 date.
204.It 10/1/2000
205October 10, 2000; the common US format.
206.It 20 Jun 1994
207.It 23jun2001
208.It 1-sep-06
209Other common abbreviations.
210.It 1/11
211the year can be omitted
212.El
213.Pp
214As well as times:
215.Bl -tag -compact
216.It 10:01
217.It 10:12pm
218.It 12:11:01.000012
219.It 12:21-0500
220.El
221.Pp
222Relative items are also supported:
223.Bl -tag -compact
224.It -1 month
225.It last friday
226.It one week ago
227.It this thursday
228.It next sunday
229.It +2 years
230.El
231.Sh RETURN VALUES
232.Fn parsedate
233returns the number of seconds passed since the Epoch, or
234.Dv \-1
235if the date could not be parsed properly.
236.Sh SEE ALSO
237.Xr date 1 ,
238.Xr eeprom 8
239.Sh HISTORY
240The parser used in
241.Fn parsedate
242was originally written by Steven M. Bellovin while at the University
243of North Carolina at Chapel Hill.
244It was later tweaked by a couple of people on Usenet.
245Completely overhauled by Rich $alz and Jim Berets in August, 1990.
246.Pp
247The
248.Fn parsedate
249function first appeared in
250.Nx 4.0 .
251