1JCTIME(3) libjalali Manual JCTIME(3)
3
7 jasctime, jctime, jgmtime, jlocaltime, jmktime, jasctime_r, jctime_r,
8 jgmtime_r, jlocaltime_r - transform jalali date and time to broken-down
9 jalali time or ASCII
10
12 #include <jtime.h>
13 char *jasctime(const struct jtm *jtm);
15 char *jasctime_r(const struct jtm *jtm, char *buf);
16 char *jctime(const time_t *timep);
18 char *jctime_r(const time_t *timep, char *buf);
19 struct jtm *jgmtime(const time_t *timep);
21 struct jtm *jgmtime_r(const time_t *timep, struct jtm *result);
22 struct jtm *jlocaltime(const time_t *timep);
24 struct jtm *jlocaltime_r(const time_t *timep, struct jtm *result);
25 time_t jmktime(struct jtm *jtm);
27 #include <jalali.h>
29 int jalali_is_jleap(int year);
31 void jalali_create_time_from_secs(time_t time, struct ab_jtm* ab_jtm);
33 time_t jalali_create_secs_from_time(const struct ab_jtm* ab_jtm);
34 int jalali_create_date_from_days(struct jtm* jtm);
36 int jalali_create_days_from_date(struct jtm* jtm);
37 void jalali_get_jyear_info(struct jyinfo* jyinfo);
39 void jalali_get_date(int p, struct jtm* jtm);
41 int jalali_get_diff(const struct jtm* jtm);
42 void jalali_update(struct jtm* jtm);
44 Link with -ljalali
47
50 The jctime(), jgmtime() and jlocaltime() functions all take an argument
51 of data type time_t which represents calendar time. When interpreted
52 as an absolute time value, it represents the number of seconds elapsed
53 since the Epoch, 1970-01-01 (1348-10-11 in Jalali) 00:00:00 +0000
54 (UTC).
55 The jasctime() and jmktime() functions both take an argument represent‐
57 ing broken-down jalali time which is a representation separated into
58 year, month, day, etc.
59 Broken-down jalali time is stored in the structure jtm which is defined
61 in <jtime.h> as follows:
62 struct jtm {
64 int tm_sec; /* seconds */
65 int tm_min; /* minutes */
66 int tm_hour; /* hours */
67 int tm_mday; /* day of the month */
68 int tm_mon; /* month */
69 int tm_year; /* year */
70 int tm_wday; /* day of the week */
71 int tm_yday; /* day in the year */
72 int tm_isdst; /* daylight saving time */
73 };
74 The members of the jtm structure are:
76 tm_sec The number of seconds after the minute, in the range 0 to 59.
78 tm_min The number of minutes after the hour, in the range 0 to 59.
80 tm_hour The number of hours past midnight, in the range 0 to 23.
82 tm_mday The day of the month, in the range 1 to 31.
84 tm_mon The number of months since Farvadin, in the range 0 to 11.
86 tm_year Absolute year number including the century.
88 tm_wday The number of days since Saturday, in the range 0 to 6.
90 tm_yday The number of days since Farvadin 1, in the range 0 to 365.
92 tm_isdst A flag that indicates whether daylight saving time is in
94 effect at the time described. The value is positive if day‐
95 light saving time is in effect, zero otherwise.
96 Information about a certain year in jalali system is stored in the
98 structure jyinfo in the following format:
99 struct jyinfo {
101 int lf; /* leap indicator flag */
102 int y; /* year */
103 int r; /* reamining years in grand cycle */
104 int p; /* passed years from grand cycle*/
105 int rl; /* remaining leap years in grand cycle */
106 int pl; /* passed leap years in grand cycle */
107 int apl; /* absolute passed leaps */
108 };
109 The members of the jyinfo structure are:
111 lf A flag that indicates whether a year is leap or not.
113 y Absolute year number including the century.
115 r The number of remaining years in the grand cycle. (2820 years
117 in length)
118 p The number of passed years in the grand cycle.
120 rl The number of remaining leap years in the grand cycle.
122 pl The number of passed leap years in the grand cycle.
124 apl The absolute number of passed leaps since Epoch.
126 Internal jalali date functions make use of passed days since UTC Epoch
128 to calculate date and time. To store these information, the following
129 structure is also defined:
130 struct ab_jtm {
132 int ab_sec;
133 int ab_min;
134 int ab_hour;
135 int ab_days;
136 };
137 The members of the ab_jtm structure are as follows:
139 ab_sec The number of seconds.
141 ab_min The number of minutes.
143 ab_hour The number of hours
145 ab_days The absolute number of days since UTC Epoch. (1348-10-11)
147 The call jctime(t) is equivalent to jasctime(jlocaltime(t)). It con‐
149 verts the calendar time t into a null-terminated string of the form
150 "Jom Kho 06 22:59:17 1390\n"
152 The abbreviations for the days of the week are "Sun", "Mon", "Tue",
154 "Wed", "Thu", "Fri", and "Sat". Farsi transliteration for the days of
155 the week are "Sha", "Yek", "Dos", "Ses", "Cha", "Pan", and "Jom". The
156 abbreviations for the months are "Far", "Ord", "Kho", "Tir", "Mor",
157 "Sha", "Meh", "Aba", "Aza", "Dey", "Bah", and "Esf". The return value
158 points to a statically allocated string which might be overwritten by
159 subsequent calls to any of the date and time functions. The reentrant
160 version jctime_r() does the same, but stores the string in a user-sup‐
161 plied buffer which should have room for at least 26 bytes.
162 The jgmtime() function converts the calendar time timep to broken-down
164 jalali time representation, expressed in Coordinated Universal Time
165 (UTC). The return value points to a statically allocated struct which
166 might be overwritten by subsequent calls to any of the jalali date and
167 time functions. The jgmtime_r() function does the same, but stores the
168 data in a user-supplied struct. The function acts as if it called
169 tzset(3)
170 The jlocaltime() function converts the calendar time timep to broken-
172 down jalali time representation, expressed relative to the user's spec‐
173 ified timezone. The function acts as if it called tzset(3) and sets
174 the external variables tzname with information about the current time‐
175 zone, timezone with the difference between Coordinated Universal Time
176 (UTC) and local standard time in seconds, and daylight to a nonzero
177 value if daylight savings time rules apply during some part of the
178 year. The return value points to a statically allocated struct which
179 might be overwritten by subsequent calls to any of the jalali date and
180 time functions. The jlocaltime_r() function does the same, but stores
181 the data in a user-supplied struct.
182 The jasctime() function converts the broken-down jalali time value jtm
184 into a null-terminated string with the same format as jctime(). The
185 return value points to a statically allocated string which might be
186 overwritten by subsequent calls to any of the date and time functions.
187 The jasctime_r() function does the same, but stores the string in a
188 user-supplied buffer which should have room for at least 26 bytes.
189 The jmktime() function converts a broken-down jalali time structure,
191 expressed as local time, to calendar time representation. The function
192 ignores the values supplied by the caller in the tm_wday field. The
193 value specified in the tm_isdst field informs jmktime() whether or not
194 daylight saving time (DST) is in effect for the time supplied in the
195 jtm structure: a positive value means DST is in effect; zero means that
196 DST is not in effect;
197 The jmktime() function modifies the fields of the jtm structure as fol‐
199 lows: tm_wday and tm_yday are set to values determined from the con‐
200 tents of the other fields; if structure members are outside their valid
201 interval, they will be normalized (so that, for example, 40 Bahman is
202 changed into 10 Esfand); Calling jmktime() also sets the external vari‐
203 able tzname with information about the current timezone.
204 jmktime() function does not check the values of the jtm structure.
206 There are a number of non-standard functions also provided to work with
209 jalali date and time.
210 The jalali_is_jleap() function returns an integer indicating whether
213 the year specified is leap or not. It returns 1 on the event of
214 encountering a leap year, 0 otherwise.
215 The jalali_create_time_from_secs() function fills out the ab_jtm struc‐
218 ture members based on the absolute number of seconds elapsed since UTC
219 Epoch.
220 The jalali_create_secs_from_time() function is the converse function to
223 jalali_create_time_from_secs() which returns absolute number of seconds
224 elapsed since UTC Epoch based on the supplied ab_jtm structure.
225 The jalali_create_date_from_days() function alters tm_mon and tm_mday
228 fields of the broken-down jalali time strucutre based on it's tm_yday
229 field. It returns -1 on the event of encountering any errors and
230 structure fields remain untouched.
231 The jalali_create_days_from_date() function alters tm_yday field of the
234 broken-down jalali time structure based on it's tm_mon and tm_mday
235 fields. It returns -1 on the event of encountering any errors and
236 structure fields remain untouched.
237 The jalali_get_jyear_info() function modifies jyinfo structure fields
240 to match information for year specified by it's y field. Information
241 regarding a year in jalali system includes leap flag, passed and
242 reamining years in the grand cycle, passed and remaining leap years in
243 the grand cycle and absolute number of passed leaps since UTC Epoch.
244 The jalali_get_date() function calculates the jalali date based on num‐
247 ber of days since UTC epoch. It alters the broken-down jalali time
248 structure fields accordingly.
249 The jalali_get_diff() function is the converse function of
252 jalali_get_date() and calculates the number of days passed since UTC
253 Epoch based on a broken-down jalali time structure supplied to it.
254 The jalali_update() function updates tm_wday and tm_yday fields of the
257 broken-down jalali time structure based on it's tm_year , tm_mon and
258 tm_mday. tm_isdst, tm_gmtoff and tm_zone fields are set accordingly.
259 tm_hour, tm_min and tm_sec fields remain untouched.
260
263 The following program converts a jalali date to gregorian
264 #include <stdio.h>
265 #include <stdlib.h>
266 #include <time.h>
267 #include <jalali.h>
268 #include <jtime.h>
269 int
271 main(int argc, char ** argv)
272 {
273 struct tm tm;
274 struct jtm jtm;
275 time_t t;
276 jtm.tm_year = atoi(argv[1]);
278 jtm.tm_mon = atoi(argv[2]);
279 jtm.tm_mday = atoi(argv[3]);
280 jalali_update(&jtm);
282 t = jmktime(&jtm);
283 localtime_r(&t, &tm);
284 printf("%d/%d/%d \n", tm.tm_year, tm.tm_mon, tm.tm_mday);
285 exit(EXIT_SUCCESS);
286 }
287
290 Each of these functions returns the value described, or NULL (-1 in
291 case of jmktime()) in case an error was detected.
292
294 C99 Standards. These functions are provided with APIs similar to that
295 of POSIX.1-2001 date and time manipulation and are NOT part of POSIX
296 standard. For thread safety jasctime(), jctime(), gmtime(), local‐
297 time(), and mktime() set of functions should nout be used. See reen‐
298 trant versions.
299 like POSIX.1-2008, the following functions: jasctime(), jasctime_r(),
301 jctime(), and jctime_r() should be considered obsolete. Use jstrf‐
302 time(3) instead.
303
305 The four functions jasctime(), jctime(), jgmtime() and jlocaltime()
306 return a pointer to static data and hence are not thread-safe. Thread-
307 safe versions are jasctime_r(), jctime_r(), jgmtime_r() and jlocal‐
308 time_r()
309 libjalali version of struct jtm has additional fields
312 long tm_gmtoff; /* Seconds east of UTC */
314 const char *tm_zone; /* Timezone abbreviation */
315
318 jdate(1), jcal(1), gettimeofday(2), time(2), utime(2), clock(3), diff‐
319 time(3), jstrftime(3), jstrptime(3), timegm(3), tzset(3), time(7)
320
322 This page is part of release 0.2 of the libjalali man-pages
323
325 Written by Ashkan Ghassemi. <ghassemi@ftml.net>
326
328 Report libjalali bugs to <ghassemi@ftml.net>
329 libjalali home page: <http://savannah.nongnu.org/projects/jcal/>
331
333 Copyright (C) 2011 Ashkan Ghassemi.
334 License LGPLv3+: GNU LGPL version 3 or later
336 <http://gnu.org/licenses/lgpl.html>. This is free software: you are
337 free to change and redistribute it. There is NO WARRANTY, to the extent
338 permitted by law.
339 2011-05-28 JCTIME(3)