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/* Layout and location of TZif files. */
#ifndef TZFILE_H
#define TZFILE_H
/*
* This file is in the public domain, so clarified as of
* 1996-06-05 by Arthur David Olson.
*
* IDENTIFICATION
* src/timezone/tzfile.h
*/
/*
* This header is for use ONLY with the time conversion code.
* There is no guarantee that it will remain unchanged,
* or that it will remain at all.
* Do NOT copy it to any system include directory.
* Thank you!
*/
/*
* Information about time zone files.
*/
#define TZDEFAULT "/etc/localtime"
#define TZDEFRULES "posixrules"
/* See Internet RFC 8536 for more details about the following format. */
/*
* Each file begins with. . .
*/
#define TZ_MAGIC "TZif"
struct tzhead
{
char tzh_magic[4]; /* TZ_MAGIC */
char tzh_version[1]; /* '\0' or '2' or '3' as of 2013 */
char tzh_reserved[15]; /* reserved; must be zero */
char tzh_ttisutcnt[4]; /* coded number of trans. time flags */
char tzh_ttisstdcnt[4]; /* coded number of trans. time flags */
char tzh_leapcnt[4]; /* coded number of leap seconds */
char tzh_timecnt[4]; /* coded number of transition times */
char tzh_typecnt[4]; /* coded number of local time types */
char tzh_charcnt[4]; /* coded number of abbr. chars */
};
/*
* . . .followed by. . .
*
* tzh_timecnt (char [4])s coded transition times a la time(2)
* tzh_timecnt (unsigned char)s types of local time starting at above
* tzh_typecnt repetitions of
* one (char [4]) coded UT offset in seconds
* one (unsigned char) used to set tm_isdst
* one (unsigned char) that's an abbreviation list index
* tzh_charcnt (char)s '\0'-terminated zone abbreviations
* tzh_leapcnt repetitions of
* one (char [4]) coded leap second transition times
* one (char [4]) total correction after above
* tzh_ttisstdcnt (char)s indexed by type; if 1, transition
* time is standard time, if 0,
* transition time is local (wall clock)
* time; if absent, transition times are
* assumed to be local time
* tzh_ttisutcnt (char)s indexed by type; if 1, transition
* time is UT, if 0, transition time is
* local time; if absent, transition
* times are assumed to be local time.
* When this is 1, the corresponding
* std/wall indicator must also be 1.
*/
/*
* If tzh_version is '2' or greater, the above is followed by a second instance
* of tzhead and a second instance of the data in which each coded transition
* time uses 8 rather than 4 chars,
* then a POSIX-TZ-environment-variable-style string for use in handling
* instants after the last transition time stored in the file
* (with nothing between the newlines if there is no POSIX representation for
* such instants).
*
* If tz_version is '3' or greater, the above is extended as follows.
* First, the POSIX TZ string's hour offset may range from -167
* through 167 as compared to the POSIX-required 0 through 24.
* Second, its DST start time may be January 1 at 00:00 and its stop
* time December 31 at 24:00 plus the difference between DST and
* standard time, indicating DST all year.
*/
/*
* In the current implementation, "tzset()" refuses to deal with files that
* exceed any of the limits below.
*/
#define TZ_MAX_TIMES 2000
/* This must be at least 17 for Europe/Samara and Europe/Vilnius. */
#define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */
#define TZ_MAX_CHARS 50 /* Maximum number of abbreviation characters */
/* (limited by what unsigned chars can hold) */
#define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */
#endif /* !defined TZFILE_H */
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