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diff --git a/man3/tzset.3 b/man3/tzset.3 deleted file mode 100644 index 8479b17b0..000000000 --- a/man3/tzset.3 +++ /dev/null @@ -1,244 +0,0 @@ -'\" t -.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" References consulted: -.\" Linux libc source code -.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) -.\" 386BSD man pages -.\" Modified Sun Jul 25 11:01:58 1993 by Rik Faith (faith@cs.unc.edu) -.\" Modified 2001-11-13, aeb -.\" Modified 2004-12-01 mtk and Martin Schulze <joey@infodrom.org> -.\" -.TH tzset 3 (date) "Linux man-pages (unreleased)" -.SH NAME -tzset, tzname, timezone, daylight \- initialize time conversion information -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <time.h> -.P -.B void tzset(void); -.P -.BI "extern char *" tzname [2]; -.BI "extern long " timezone ; -.BI "extern int " daylight ; -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR tzset (): -.nf - _POSIX_C_SOURCE -.fi -.P -.IR tzname : -.nf - _POSIX_C_SOURCE -.fi -.P -.IR timezone , -.IR daylight : -.nf - _XOPEN_SOURCE - || /* glibc >= 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _SVID_SOURCE -.fi -.SH DESCRIPTION -The -.BR tzset () -function initializes the \fItzname\fP variable from the -.B TZ -environment variable. -This function is automatically called by the -other time conversion functions that depend on the timezone. -In a System-V-like environment, it will also set the variables \fItimezone\fP -(seconds West of UTC) and \fIdaylight\fP (to 0 if this timezone does not -have any daylight saving time rules, or to nonzero if there is a time, -past, present, or future when daylight saving time applies). -.P -If the -.B TZ -variable does not appear in the environment, the system timezone is used. -The system timezone is configured by copying, or linking, a file in the -.BR tzfile (5) -format to -.IR /etc/localtime . -A timezone database of these files may be located in the system -timezone directory (see the \fBFILES\fP section below). -.P -If the -.B TZ -variable does appear in the environment, but its value is empty, -or its value cannot be interpreted using any of the formats specified -below, then Coordinated Universal Time (UTC) is used. -.P -The value of -.B TZ -can be one of two formats. -The first format is a string of characters that directly represent the -timezone to be used: -.P -.in +4n -.EX -.IR "std offset" [ dst [ offset ][, start [ /time ], end [ /time ]]] -.EE -.in -.P -There are no spaces in the specification. -The \fIstd\fP string specifies an abbreviation for the timezone and must be -three or more alphabetic characters. -When enclosed between the less-than (<) and greater-than (>) signs, the -character set is expanded to include the plus (+) sign, the minus (\-) -sign, and digits. -The \fIoffset\fP string immediately -follows \fIstd\fP and specifies the time value to be added to the local -time to get Coordinated Universal Time (UTC). -The \fIoffset\fP is positive -if the local timezone is west of the Prime Meridian and negative if it is -east. -The hour must be between 0 and 24, and the minutes and seconds 00 and 59: -.P -.in +4n -.EX -.RI [ + | \- ] hh [ :mm [ :ss ]] -.EE -.in -.P -The \fIdst\fP string and \fIoffset\fP specify the name and offset for the -corresponding daylight saving timezone. -If the offset is omitted, -it defaults to one hour ahead of standard time. -.P -The \fIstart\fP field specifies when daylight saving time goes into -effect and the \fIend\fP field specifies when the change is made back to -standard time. -These fields may have the following formats: -.TP -J\fIn\fP -This specifies the Julian day with \fIn\fP between 1 and 365. -Leap days are not counted. -In this format, February 29 can't be represented; -February 28 is day 59, and March 1 is always day 60. -.TP -.I n -This specifies the zero-based Julian day with \fIn\fP between 0 and 365. -February 29 is counted in leap years. -.TP -M\fIm\fP.\fIw\fP.\fId\fP -This specifies day \fId\fP (0 <= \fId\fP <= 6) of week \fIw\fP -(1 <= \fIw\fP <= 5) of month \fIm\fP (1 <= \fIm\fP <= 12). -Week 1 is -the first week in which day \fId\fP occurs and week 5 is the last week -in which day \fId\fP occurs. -Day 0 is a Sunday. -.P -The \fItime\fP fields specify when, in the local time currently in effect, -the change to the other time occurs. -If omitted, the default is 02:00:00. -.P -Here is an example for New Zealand, -where the standard time (NZST) is 12 hours ahead of UTC, -and daylight saving time (NZDT), 13 hours ahead of UTC, -runs from the first Sunday in October to the third Sunday in March, -and the changeovers happen at the default time of 02:00:00: -.P -.in +4n -.EX -TZ="NZST\-12:00:00NZDT\-13:00:00,M10.1.0,M3.3.0" -.EE -.in -.P -The second format specifies that the timezone information should be read -from a file: -.P -.in +4n -.EX -:[filespec] -.EE -.in -.P -If the file specification \fIfilespec\fP is omitted, or its value cannot -be interpreted, then Coordinated Universal Time (UTC) is used. -If \fIfilespec\fP is given, it specifies another -.BR tzfile (5)-format -file to read the timezone information from. -If \fIfilespec\fP does not begin with a \[aq]/\[aq], the file specification is -relative to the system timezone directory. -If the colon is omitted each -of the above \fBTZ\fP formats will be tried. -.P -Here's an example, once more for New Zealand: -.P -.in +4n -.EX -TZ=":Pacific/Auckland" -.EE -.in -.SH ENVIRONMENT -.TP -.B TZ -If this variable is set its value takes precedence over the system -configured timezone. -.TP -.B TZDIR -If this variable is set its value takes precedence over the system -configured timezone database directory path. -.SH FILES -.TP -.I /etc/localtime -The system timezone file. -.TP -.I /usr/share/zoneinfo/ -The system timezone database directory. -.TP -.I /usr/share/zoneinfo/posixrules -When a TZ string includes a dst timezone without anything following it, -then this file is used for the start/end rules. -It is in the -.BR tzfile (5) -format. -By default, the zoneinfo Makefile hard links it to the -.IR America/New_York " tzfile." -.P -Above are the current standard file locations, but they are -configurable when glibc is compiled. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR tzset () -T} Thread safety MT-Safe env locale -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, SVr4, 4.3BSD. -.P -4.3BSD had a function -.BI "char *timezone(" zone ", " dst ) -that returned the -name of the timezone corresponding to its first argument (minutes -West of UTC). -If the second argument was 0, the standard name was used, -otherwise the daylight saving time version. -.SH SEE ALSO -.BR date (1), -.BR gettimeofday (2), -.BR time (2), -.BR ctime (3), -.BR getenv (3), -.BR tzfile (5) |