diff options
author | wollman <wollman@FreeBSD.org> | 1999-01-21 17:22:59 +0000 |
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committer | wollman <wollman@FreeBSD.org> | 1999-01-21 17:22:59 +0000 |
commit | eb63a8058f661b6501ad66d148ede682ec3c7ca9 (patch) | |
tree | d1ca153fcab31c4db9b282be4abde93b0da2271a /lib/libc/stdtime/tzfile.5 | |
parent | 78cf17718823a5a0f70549acd4e7c7cd8b209fbb (diff) | |
download | FreeBSD-src-eb63a8058f661b6501ad66d148ede682ec3c7ca9.zip FreeBSD-src-eb63a8058f661b6501ad66d148ede682ec3c7ca9.tar.gz |
Merge from vendor branch: timezone file structure changes and doco.
Fix localtime.c to deal with new magic number field.
Obtained from: ftp://elsie.nci.nih.gov/pub/tzcode1999a.tar.gz
Diffstat (limited to 'lib/libc/stdtime/tzfile.5')
-rw-r--r-- | lib/libc/stdtime/tzfile.5 | 55 |
1 files changed, 36 insertions, 19 deletions
diff --git a/lib/libc/stdtime/tzfile.5 b/lib/libc/stdtime/tzfile.5 index 880e3af..946ae48 100644 --- a/lib/libc/stdtime/tzfile.5 +++ b/lib/libc/stdtime/tzfile.5 @@ -1,15 +1,20 @@ +.\" $Id: tzfile.5,v 1.6 1999/01/20 18:54:12 wollman Exp $ .Dd September 13, 1994 .Dt TZFILE 5 -.Os FreeBSD 2.0 +.Os FreeBSD 3.0 .Sh NAME .Nm tzfile .Nd timezone information .Sh SYNOPSIS -.Fd #include <tzfile.h> +.Fd #include "/usr/src/lib/libc/stdtime/tzfile.h" .Sh DESCRIPTION The time zone information files used by .Xr tzset 3 -begin with bytes reserved for future use, +begin with the magic characters +.Dq Li TZif +to identify them as +time zone information files, +followed by sixteen bytes reserved for future use, followed by four four-byte values written in a ``standard'' byte order (the high-order byte of the value is written first). @@ -17,23 +22,25 @@ These values are, in order: .Pp .Bl -tag -compact -width tzh_ttisstdcnt -.It Li tzh_ttisstdcnt +.It Va tzh_ttisgmtcnt +The number of UTC/local indicators stored in the file. +.It Va tzh_ttisstdcnt The number of standard/wall indicators stored in the file. -.It Li tzh_leapcnt +.It Va tzh_leapcnt The number of leap seconds for which data is stored in the file. -.It Li tzh_timecnt +.It Va tzh_timecnt The number of ``transition times'' for which data is stored in the file. -.It Li tzh_typecnt +.It Va tzh_typecnt The number of ``local time types'' for which data is stored in the file (must not be zero). -.It Li tzh_charcnt +.It Va tzh_charcnt The number of characters of ``time zone abbreviation strings'' stored in the file. .El .Pp The above header is followed by -.Li tzh_timecnt +.Va tzh_timecnt four-byte values of type .Fa long , sorted in ascending order. @@ -42,7 +49,7 @@ Each is used as a transition time (as returned by .Xr time 3 ) at which the rules for computing local time change. Next come -.Li tzh_timecnt +.Va tzh_timecnt one-byte values of type .Fa "unsigned char" ; each one tells which of the different types of ``local time'' types @@ -61,30 +68,30 @@ struct ttinfo { .Ed .Pp Each structure is written as a four-byte value for -.Li tt_gmtoff +.Va tt_gmtoff of type .Fa long , in a standard byte order, followed by a one-byte value for -.Li tt_isdst +.Va tt_isdst and a one-byte value for -.Li tt_abbrind . +.Va tt_abbrind . In each structure, -.Li tt_gmtoff -gives the number of seconds to be added to GMT, +.Va tt_gmtoff +gives the number of seconds to be added to UTC, .Li tt_isdst tells whether .Li tm_isdst should be set by .Xr localtime 3 and -.Li tt_abbrind +.Va tt_abbrind serves as an index into the array of time zone abbreviation characters that follow the .Li ttinfo structure(s) in the file. .Pp Then there are -.Li tzh_leapcnt +.Va tzh_leapcnt pairs of four-byte values, written in standard byte order; the first value of each pair gives the time (as returned by @@ -95,14 +102,22 @@ the second gives the number of leap seconds to be applied after the given time. The pairs of values are sorted in ascending order by time. .Pp -Finally there are -.Li tzh_ttisstdcnt +Then there are +.Va tzh_ttisstdcnt standard/wall indicators, each stored as a one-byte value; they tell whether the transition times associated with local time types were specified as standard time or wall clock time, and are used when a time zone file is used in handling POSIX-style time zone environment variables. .Pp +Finally there are +.Va tzh_ttisgmtcnt +UTC/local indicators, each stored as a one-byte value; +they tell whether the transition times associated with local time types +were specified as UTC or local time, +and are used when a time zone file is used in handling POSIX-style +time zone environment variables. +.Pp .Nm localtime uses the first standard-time .Li ttinfo @@ -119,3 +134,5 @@ in the file. .Xr time2posix 3 , .Xr zic 8 .\" @(#)tzfile.5 7.2 +.\" This file is in the public domain, so clarified as of +.\" 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov). |