Paul,
On 06/27/2018 09:52 PM, Paul Eggert wrote:
> Make tzfile.5 a copy of the upstream tzdb version, except that
> the tzdb version's first line is replaced by man-pages
> boilerplate.
>
> This has the following effect:
>
> Do some minor spec fixes, notably about time type 0
> and empty TZ strings. Omit some changes that were made on the
> man-pages side, notably by changing some "timezone"s back to the
> preferred-upstream "time zone" when talking about traditional
> time zones as opposed to POSIX timezone settings.
> Also, fix some formatting glitches.
My apologies for the long delay in following up.
Patch applied.
Cheers,
Michael
> ---
> man5/tzfile.5 | 49 ++++++++++++++++++++++++++++---------------------
> 1 file changed, 28 insertions(+), 21 deletions(-)
>
> diff --git a/man5/tzfile.5 b/man5/tzfile.5
> index 46e083930..7c129e200 100644
> --- a/man5/tzfile.5
> +++ b/man5/tzfile.5
> @@ -3,8 +3,6 @@
> .\" 1996-06-05 by Arthur David Olson <arthur_david_olson@xxxxxxx>.
> .\" %%%LICENSE_END
> .\"
> -.\" @(#)tzfile.5 7.11
> -.\"
> .TH TZFILE 5 2017-08-04 "" "Linux Programmer's Manual"
> .SH NAME
> tzfile \- timezone information
> @@ -59,12 +57,12 @@ The number of local time types for which data entries are stored
> in the file (must not be zero).
> .TP
> .I tzh_charcnt
> -The number of bytes of timezone abbreviation strings
> +The number of bytes of time zone abbreviation strings
> stored in the file.
> .RE
> .PP
> The above header is followed by the following fields, whose lengths
> -vary depend on the contents of the header:
> +depend on the contents of the header:
> .IP * 2
> .I tzh_timecnt
> four-byte signed integer values sorted in ascending order.
> @@ -75,25 +73,29 @@ at which the rules for computing local time change.
> .IP *
> .I tzh_timecnt
> one-byte unsigned integer values;
> -each one tells which of the different types of local time types
> +each one but the last tells which of the different types of local time types
> described in the file is associated with the time period
> -starting with the same-indexed transition time.
> +starting with the same-indexed transition time
> +and continuing up to but not including the next transition time.
> +(The last time type is present only for consistency checking with the
> +POSIX-style TZ string described below.)
> These values serve as indices into the next field.
> .IP *
> .I tzh_typecnt
> .I ttinfo
> entries, each defined as follows:
> -.PP
> -.in +4n
> -.EX
> +.in +.5i
> +.sp
> +.nf
> +.ta .5i +\w'unsigned char\0\0'u
> struct ttinfo {
> - int32_t tt_gmtoff;
> - unsigned char tt_isdst;
> - unsigned char tt_abbrind;
> + int32_t tt_gmtoff;
> + unsigned char tt_isdst;
> + unsigned char tt_abbrind;
> };
> -.EE
> -.in
> -.PP
> +.in -.5i
> +.fi
> +.sp
> Each structure is written as a four-byte signed integer value for
> .IR tt_gmtoff ,
> in a standard byte order, followed by a one-byte value for
> @@ -110,7 +112,7 @@ should be set by
> .BR localtime (3)
> and
> .I tt_abbrind
> -serves as an index into the array of timezone abbreviation bytes
> +serves as an index into the array of time zone abbreviation bytes
> that follow the
> .I ttinfo
> structure(s) in the file.
> @@ -165,21 +167,26 @@ eight bytes are used for each transition time or leap second time.
> After the second header and data comes a newline-enclosed,
> 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).
> -The POSIX-style string must agree with the local time type after
> -both data's last transition times; for example, given the string
> +or for all instants if the file has no transitions.
> +The POSIX-style TZ string is empty (i.e., nothing between the newlines)
> +if there is no POSIX representation for such instants.
> +If nonempty, the POSIX-style TZ string must agree with the local time
> +type after the last transition time if present in the eight-byte data;
> +for example, given the string
> .q "WET0WEST,M3.5.0,M10.5.0/3"
> then if a last transition time is in July, the transition's local time
> type must specify a daylight-saving time abbreviated
> .q "WEST"
> that is one hour east of UT.
> +Also, if there is at least one transition, time type 0 is associated
> +with the time period from the indefinite past up to but not including
> +the earliest transition time.
> .SS Version 3 format
> For version-3-format timezone files, the POSIX-TZ-style string may
> use two minor extensions to the POSIX TZ format, as described in
> .BR newtzset (3).
> First, the hours part of its transition times may be signed and range from
> -\-167 through 167 instead of the POSIX-required unsigned values
> +\*-167 through 167 instead of the POSIX-required unsigned values
> from 0 through 24.
> Second, DST is in effect all year if it starts
> January 1 at 00:00 and ends December 31 at 24:00 plus the difference
>
--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/
