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Diffstat (limited to 'unused/newtzset.3.txt')
| -rw-r--r-- | unused/newtzset.3.txt | 153 |
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diff --git a/unused/newtzset.3.txt b/unused/newtzset.3.txt new file mode 100644 index 000000000000..9d7d02233ee0 --- /dev/null +++ b/unused/newtzset.3.txt @@ -0,0 +1,153 @@ +NAME + + tzset - initialize time conversion information + +SYNOPSIS + void tzset() + + cc ... -ltz + +DESCRIPTION + Tzset uses the value of the environment variable TZ to set + time conversion information used by localtime. If TZ does + not appear in the environment, the best available + approximation to local wall clock time, as specified by the + tzfile(5)-format file localtime in the system time + conversion information directory, is used by localtime. If + TZ appears in the environment but its value is a null + string, Coordinated Universal Time (UTC) is used (without + leap second correction). If TZ appears in the environment + and its value is not a null string: + + if the value begins with a colon, it is used as a + pathname of a file from which to read the time + conversion information; + + if the value does not begin with a colon, it is first + used as the pathname of a file from which to read the + time conversion information, and, if that file cannot + be read, is used directly as a specification of the + time conversion information. + + When TZ is used as a pathname, if it begins with a slash, it + is used as an absolute pathname; otherwise, it is used as a + pathname relative to a system time conversion information + directory. The file must be in the format specified in + tzfile(5). + + When TZ is used directly as a specification of the time + conversion information, it must have the following syntax + (spaces inserted for clarity): + + stdoffset[dst[offset][,rule]] + + Where: + + std and dst Three or more bytes that are the + designation for the standard (std) or + summer (dst) time zone. Only std is + required; if dst is missing, then summer + time does not apply in this locale. + Upper- and lowercase letters are + explicitly allowed. Any characters + except a leading colon (:), digits, + comma (,), minus (-), plus (+), and + ASCII NUL are allowed. + + offset Indicates the value one must add to the + local time to arrive at Coordinated + Universal Time. The offset has the + form: + + hh[:mm[:ss]] + + The minutes (mm) and seconds (ss) are + optional. The hour (hh) is required and + may be a single digit. The offset + following std is required. If no offset + follows dst, summer time is assumed to + be one hour ahead of standard time. One + or more digits may be used; the value is + always interpreted as a decimal number. + The hour must be between zero and 24, + and the minutes (and seconds) -- if + present -- between zero and 59. If + preceded by a ``-'', the time zone shall + be east of the Prime Meridian; otherwise + it shall be west (which may be indicated + by an optional preceding ``+''). + + rule Indicates when to change to and back + from summer time. The rule has the + form: + + date/time,date/time + + where the first date describes when the + change from standard to summer time + occurs and the second date describes + when the change back happens. Each time + field describes when, in current local + time, the change to the other time is + made. + + The format of date is one of the + following: + + Jn The Julian day n + (1 <= n <= 365). Leap days + are not counted; that is, in + all years -- including leap + years -- February 28 is day 59 + and March 1 is day 60. It is + impossible to explicitly refer + to the occasional February 29. + + n The zero-based Julian day + (0 <= n <= 365). Leap days + are counted, and it is + possible to refer to February + 29. + + Mm.n.d The d'th day (0 <= d <= 6) of + week n of month m of the year + (1 <= n <= 5, 1 <= m <= 12, + where week 5 means ``the last + d day in month m'' which may + occur in either the fourth or + the fifth week). Week 1 is + the first week in which the + d'th day occurs. Day zero is + Sunday. + + The time has the same format as offset + except that no leading sign (``-'' or + ``+'') is allowed. The default, if time + is not given, is 02:00:00. + + If no rule is present in TZ, the rules specified by the + tzfile(5)-format file posixrules in the system time + conversion information directory are used, with the standard + and summer time offsets from UTC replaced by those specified + by the offset values in TZ. + For compatibility with System V Release 3.1, a semicolon (;) + may be used to separate the rule from the rest of the + specification. + + If the TZ environment variable does not specify a + tzfile(5)-format and cannot be interpreted as a direct + specification, UTC is used. + +FILES + /usr/local/etc/zoneinfo time zone information + directory + /usr/local/etc/zoneinfo/localtime local time zone file + /usr/local/etc/zoneinfo/posixrules used with POSIX-style + TZ's + /usr/local/etc/zoneinfo/GMT for UTC leap seconds + + If /usr/local/etc/zoneinfo/GMT is absent, UTC leap seconds + are loaded from /usr/local/etc/zoneinfo/posixrules. + +SEE ALSO + getenv(3), newctime(3), newstrftime(3), time(2), tzfile(5) |