- tz - lists.iana.org

error Portugal 1980
by Alois Treindl July 2, 2024

July 2, 2024

I think there is an error in TZ, regarding begin of DST in Portugal in 1980. A user of my website pointed it out. file europe has > Rule Port 1978 only - Oct 1 0:00s 0 - > Rule Port 1979 1982 - Sep lastSun 1:00s 0 - > Rule Port 1980 only - Mar lastSun 0:00s 1:00 S > Rule Port 1981 1982 - Mar lastSun 1:00s 1:00 S > Rule Port 1983 only - Mar lastSun 2:00s 1:00 S But Observatório Astronómico de Lisboa http://oal.ul.pt/hora-legal/legislacao-sobre-a-hora-legal/ has in document Tabela com a definição anual da Hora Legal portuguesa desde 1911 https://oal.ul.pt/documentos/2018/01/hl1911a2018.pdf > 1980 Hora do meridiano de Greenwich até à 1 hora do dia 6 de Abril, > instante > em que foi adiantada de 60 minutos, tendo-se regressado à hiora do meri- > diano de Greenwich às 2 horas do dia 28 de Setembro (Portaria nº 69/80) > I attach a patch file

4 12

[PROPOSED] More documentation updates for POSIX.1-2024
by Paul Eggert June 16, 2024

June 16, 2024

Be more careful when documenting tm_zone, tm_gmtoff, tzname, etc., in the light of POSIX.1-2024 etc. --- Makefile | 8 ++++-- newctime.3 | 79 ++++++++++++++++++++++++--------------------------- newstrftime.3 | 14 ++++----- newtzset.3 | 55 +++++++++++++++++++++++++++++++---- 4 files changed, 100 insertions(+), 56 deletions(-) diff --git a/Makefile b/Makefile index 99f2f56b..d6d66a1f 100644 --- a/Makefile +++ b/Makefile @@ -358,7 +358,9 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 \ # # -DHAVE_TZNAME=0 # do not support "tzname" # # -DHAVE_TZNAME=1 # support "tzname", which is defined by system library # # -DHAVE_TZNAME=2 # support and define "tzname" -# # to the "CFLAGS=" line. "tzname" is required by POSIX.1-1988 and later. +# # to the "CFLAGS=" line. Although "tzname" is required by POSIX.1-1988 +# # and later, its contents are unspecified if you use a geographical TZ +# # and the variable is planned to be removed in a future POSIX edition. # # If not defined, the code attempts to guess HAVE_TZNAME from other macros. # # Warning: unless time_tz is also defined, HAVE_TZNAME=1 can cause # # crashes when combined with some platforms' standard libraries, @@ -369,7 +371,9 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 \ # # -DUSG_COMPAT=1 # support, and variables are defined by system library # # -DUSG_COMPAT=2 # support and define variables # # to the "CFLAGS=" line; "timezone" and "daylight" are inspired by Unix -# # Systems Group code and are required by POSIX.1-2008 and later (with XSI). +# # Systems Group code and are required by POSIX.1-2008 and later (with XSI), +# # although their contents are unspecified if you use a geographical TZ +# # and the variables are planned to be rmeoved in a future edition of POSIX. # # If not defined, the code attempts to guess USG_COMPAT from other macros. # # # # To support the external variable "altzone", add diff --git a/newctime.3 b/newctime.3 index ccc19748..d19fd25b 100644 --- a/newctime.3 +++ b/newctime.3 @@ -9,8 +9,6 @@ asctime, ctime, difftime, gmtime, localtime, mktime \- convert date and time .el .ds - \- .B #include <time.h> .PP -.BR "extern char *tzname[];" " /\(** (optional) \(**/" -.PP .B [[deprecated]] char *ctime(time_t const *clock); .PP /* Only in POSIX.1-2017 and earlier. */ @@ -114,17 +112,6 @@ The function corrects for the time zone and any time zone adjustments (such as Daylight Saving Time in the United States). -After filling in the -.q "tm" -structure, -.B localtime -sets the -.BR tm_isdst 'th -element of -.B tzname -to a pointer to a string that's the time zone abbreviation to be used with -.BR localtime 's -return value. .PP The .B gmtime @@ -294,21 +281,43 @@ from UT, with positive values indicating east of the Prime Meridian. The field's name is derived from Greenwich Mean Time, a precursor of UT. .PP -In +In platforms conforming to POSIX.1-2024 the .B "struct tm" the .B tm_zone and .B tm_gmtoff -fields exist, and are filled in, only if arrangements to do -so were made when the library containing these functions was -created. -Similarly, the -.B tzname -variable is optional; also, there is no guarantee that -.B tzname -will -continue to exist in this form in future releases of this code. +fields exist, and are filled in. +For +.B localtime_rz +and +.B mktime_rz +the storage lifetime of the strings addressed by +.B tm_zone +extends until the corresponding +.B timezone_t +object is freed via +.BR tzfree . +For the other functions the lifetime extends until the +.I TZ +environment variable changes state and +.B tzset +is then called. +.PP +As a side effect, the +.BR ctime , +.B localtime +and +.B mktime +functions also behave as if +.B tzset +were called. +The +.B ctime_r +and +.B localtime_r +functions might (or might not) also behave this way. +This is for compatibility with older platforms, as required by POSIX. .SH FILES .ta \w'/usr/share/zoneinfo/posixrules\0\0'u /etc/localtime local timezone file @@ -322,11 +331,11 @@ continue to exist in this form in future releases of this code. If /usr/share/zoneinfo/GMT is absent, UTC leap seconds are loaded from /usr/share/zoneinfo/GMT0 if present. .SH SEE ALSO -getenv(3), -newstrftime(3), -newtzset(3), -time(2), -tzfile(5) +.BR getenv (3), +.BR newstrftime (3), +.BR newtzset (3), +.BR time (2), +.BR tzfile (5). .SH NOTES The return values of .BR asctime , @@ -336,20 +345,6 @@ and .B localtime point to static data overwritten by each call. -The -.B tzname -variable (once set) and the -.B tm_zone -field of a returned -.B "struct tm" -both point to an array of characters that -can be freed or overwritten by later calls to the functions -.BR localtime , -.BR tzfree , -and -.BR tzset , -if these functions affect the timezone information that specifies the -abbreviation in question. The remaining functions and data are thread-safe. .PP The diff --git a/newstrftime.3 b/newstrftime.3 index 11e37ae8..a9997a09 100644 --- a/newstrftime.3 +++ b/newstrftime.3 @@ -398,7 +398,7 @@ also behaves as if were called. This is for compatibility with older platforms, as required by POSIX; it is not needed for -.BR tzset 's +.BR strftime 's own use. .SH "RETURN VALUE" If the conversion is successful, @@ -428,11 +428,11 @@ conversion and the number of seconds since the Epoch cannot be represented in a .c time_t . .SH SEE ALSO -date(1), -getenv(3), -newctime(3), -newtzset(3), -time(2), -tzfile(5) +.BR date (1), +.BR getenv (3), +.BR newctime (3), +.BR newtzset (3), +.BR time (2), +.BR tzfile (5). .SH BUGS There is no conversion specification for the phase of the moon. diff --git a/newtzset.3 b/newtzset.3 index 4708106d..661fb25b 100644 --- a/newtzset.3 +++ b/newtzset.3 @@ -15,6 +15,14 @@ tzset \- initialize time conversion information .PP .B void tzset(void); .PP +/\(** Optional and obsolescent: \(**/ +.br +.B extern char *tzname[]; +.br +.B extern long timezone; +.br +.B extern int daylight; +.PP .B cc ... \*-ltz .fi .SH DESCRIPTION @@ -341,6 +349,22 @@ if the implied call to fails, .B tzset falls back on UT. +.PP +As a side effect, the +.B tzset +function sets some external variables if the platform defines them. +It sets +.BR tzname [0] +and +.BR tzname [1] +to pointers to strings that are time zone abbreviations to be used with +standard and daylight saving time, respectively. +It also sets +.B timezone +to be the number of seconds that standard time is west of the Prime Meridian, +and +.B daylight +to be zero if daylight saving time is never in effect, non-zero otherwise. .SH "RETURN VALUE" If successful, the .B tzalloc @@ -379,8 +403,29 @@ and If /usr/share/zoneinfo/GMT is absent, UTC leap seconds are loaded from /usr/share/zoneinfo/GMT0 if present. .SH SEE ALSO -getenv(3), -newctime(3), -newstrftime(3), -time(2), -tzfile(5) +.BR getenv (3), +.BR newctime (3), +.BR newstrftime (3), +.BR time (2), +.BR tzfile (5). +.SH NOTES +Portable code should not rely on the contents of the external variables +.BR tzname , +.B timezone +and +.B daylight +as their contents are unspecified (and do not make sense in general) +when a geographical TZ is used. +In multithreaded applications behavior is undefined if one thread accesses +one of these variables while another thread invokes +.BR tzset . +A future version of POSIX is planned to remove these variables; +callers can instead use the +.I tm_gmtoff +and +.I tm_zone +members of +.B struct tm, +or use +.B strftime +with "%z" or "%Z". -- 2.43.0

2 2

[PROPOSED 1/3] Fix typo when making .txt man pages
by Paul Eggert June 12, 2024

June 12, 2024

* Makefile (MANTXTS): Fix typo: missing ‘:’. --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index c00eb317..344bb8ed 100644 --- a/Makefile +++ b/Makefile @@ -1054,7 +1054,7 @@ zdump.8.txt: zdump.8 zic.8.txt: zic.8 $(MANTXTS): workman.sh - LC_ALL=C sh workman.sh $(@.txt=) >$@.out + LC_ALL=C sh workman.sh $(@:.txt=) >$@.out mv $@.out $@ # Set file timestamps deterministically if possible, -- 2.43.0

1 2

[PROPOSED] SUPPORT_C89 now defaults to 1, not 0
by Paul Eggert June 8, 2024

June 8, 2024

Although POSIX requires this, I didn’t notice it until today. * Makefile, NEWS, localtime.c: Mention this. * private.h (SUPPORT_C89): Default to 1, not 0. --- Makefile | 5 +++-- NEWS | 4 ++++ localtime.c | 5 +++-- private.h | 17 ++++++++++------- 4 files changed, 20 insertions(+), 11 deletions(-) diff --git a/Makefile b/Makefile index 97a88535..c00eb317 100644 --- a/Makefile +++ b/Makefile @@ -263,8 +263,9 @@ LDLIBS= # -DRESERVE_STD_EXT_IDS if your platform reserves standard identifiers # with external linkage, e.g., applications cannot define 'localtime'. # -Dssize_t=long on hosts like MS-Windows that lack ssize_t -# -DSUPPORT_C89 if the tzcode library should support C89 callers+ -# However, this might trigger latent bugs in C99-or-later callers. +# -DSUPPORT_C89=0 if the tzcode library should not support C89 callers +# Although -DSUPPORT_C89=0 might work around latent bugs in callers, +# it does not conform to POSIX. # -DSUPPORT_POSIX2008 if the library should support older POSIX callers+ # However, this might cause problems in POSIX.1-2024-or-later callers. # -DSUPPRESS_TZDIR to not prepend TZDIR to file names; this has diff --git a/NEWS b/NEWS index 6b71212c..5238cb9e 100644 --- a/NEWS +++ b/NEWS @@ -8,6 +8,7 @@ Unreleased, experimental changes The code now conforms to RFC 8536 for early timestamps. Support POSIX.1-2024, which removes asctime_r and ctime_r. Assume POSIX.2-1992 or later for shell scripts. + SUPPORT_C89 now defaults to 1. Improve historical data for Portugal and possessions. Changes to data @@ -60,6 +61,9 @@ Unreleased, experimental changes can overrun user buffers. If you still need them, add -DSUPPORT_POSIX2008 to CFLAGS. + The SUPPORT_C89 option now defaults to 1 instead of 0, fixing a + POSIX-conformance bug introduced in 2023a. + tzselect now assumes POSIX.2-1992 or later, as practical porting targets now all support this. Also, tzselect uses some features from POSIX.1-2024 if available. diff --git a/localtime.c b/localtime.c index c9f0d1a8..7e3fd149 100644 --- a/localtime.c +++ b/localtime.c @@ -182,8 +182,9 @@ static int lcl_is_set; ** objects: a broken-down time structure and an array of char. ** Thanks to Paul Eggert for noting this. ** -** This requirement was removed in C99, so support it only if requested, -** as support is more likely to lead to bugs in badly written programs. +** Although this requirement was removed in C99 it is still present in POSIX. +** Follow the requirement if SUPPORT_C89, even though this is more likely to +** trigger latent bugs in programs. */ #if SUPPORT_C89 diff --git a/private.h b/private.h index 0c91a252..19d7f7d6 100644 --- a/private.h +++ b/private.h @@ -19,19 +19,22 @@ /* PORT_TO_C89 means the code should work even if the underlying compiler and library support only C89 plus C99's 'long long' - and perhaps a few other extensions to C89. SUPPORT_C89 means the - tzcode library should support C89 callers in addition to the usual - support for C99-and-later callers; however, C89 support can trigger - latent bugs in C99-and-later callers. These macros are obsolescent, - and the plan is to remove them along with any code needed only when - they are nonzero. A good time to do that might be in the year 2029 + and perhaps a few other extensions to C89. + + This macro is obsolescent, and the plan is to remove it along with + associated code. A good time to do that might be in the year 2029 because RHEL 7 (whose GCC defaults to C89) extended life cycle support (ELS) is scheduled to end on 2028-06-30. */ #ifndef PORT_TO_C89 # define PORT_TO_C89 0 #endif + +/* SUPPORT_C89 means the tzcode library should support C89 callers + in addition to the usual support for C99-and-later callers. + This defaults to 1 as POSIX requires, even though that can trigger + latent bugs in callers. */ #ifndef SUPPORT_C89 -# define SUPPORT_C89 0 +# define SUPPORT_C89 1 #endif #ifndef __STDC_VERSION__ -- 2.43.0

2 1

[PROPOSED 00/12] Assume POSIX.2-1992
by Paul Eggert June 1, 2024

June 1, 2024

For many years we have maintained code in tzselect and Makefile intended to port to older platforms that predate POSIX.2-1992. The only remaining such platform that is still supported by its supplier is Solaris 10 (2005), which has a shell and related tools that are still pre-POSIX by default, although POSIX variants are available. However, I recently discovered that Solaris 10’s own copy of tzselect now uses POSIX.2-1992 features and is based on the POSIX variants. Now that even Oracle has abandoned its pre-POSIX environment for TZDB, it’s time for us to follow suit. This series of patches updates the Makefile and tzselect shell script to assume POSIX.2-1992 or later. This simplifies maintenance and speeds up the code a bit. Paul Eggert (12): Assume POSIX.2 and eschew ‘expr’ Prefer $(CMD) to `CMD` in Makefile Prefer $PWD to $(pwd) in Makefile Avoid subshells when possible Assume POSIX.2 command substitution * tzselect.ksh: Assume POSIX.2 $PWD. * tzselect.ksh: Assume POSIX.2 awk. Avoid some subshells in tzselect Avoid an awk invocation via $'...' Use ‘export VAR=VAL’ syntax Avoid crash in Solaris 10 /usr/xpg4/bin/make Port ! to Solaris make .gitignore | 4 +- Makefile | 343 +++++++++++++++++++++++++-------------------------- NEWS | 9 ++ checknow.awk | 2 +- tzselect.ksh | 112 +++++++---------- workman.sh | 3 +- 6 files changed, 231 insertions(+), 242 deletions(-) -- 2.45.1

1 12

[PROPOSED] difftime isn’t pure either
by Paul Eggert May 28, 2024

May 28, 2024

See <https://sourceware.org/bugzilla/show_bug.cgi?id=31808#c1>. * private.h (difftime): No longer pure. --- private.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/private.h b/private.h index cacbe444..0c91a252 100644 --- a/private.h +++ b/private.h @@ -702,7 +702,7 @@ DEPRECATED_IN_C23 char *ctime(time_t const *); char *asctime_r(struct tm const *restrict, char *restrict); char *ctime_r(time_t const *, char *); #endif -ATTRIBUTE_PURE double difftime(time_t, time_t); +double difftime(time_t, time_t); size_t strftime(char *restrict, size_t, char const *restrict, struct tm const *restrict); # if HAVE_STRFTIME_L -- 2.45.1

1 0

Unicode CLDR supplemental/windowsZones.xml update? -Brooks Harris
by Brooks Harris May 28, 2024

May 28, 2024

Does someone know if the Unicode CLDR ../supplemental/windowsZones.xml has been updated? Following the best links I know to find: Unicode CLDR Overview https://cldr.unicode.org/index/downloads/cldr-45 Downloads https://cldr.unicode.org/index/downloads GitHub Tag https://raw.githubusercontent.com/RobThree/TimeZoneMapper/master/TimeZoneMa… This file says it corresponds with TzDb 2021a. Yet other notes say Windows zone were updated to TzDb 2024a: CLDR 45 Release Note https://cldr.unicode.org/index/downloads/cldr-45 Timezones Deprecating timezones that are no longer in zone.tab (America/Nipigon, ...) New Windows timezone mappings Was this file not actually updated or am I looking in the wrong place? Thanks, -Brooks

4 6

[PROPOSED 1/4] More updates to GCC_DEBUG_FLAGS for GCC 14
by Paul Eggert May 27, 2024

May 27, 2024

* Makefile (GCC_DEBUG_FLAGS): Omit -fno-common, as it is now the default. Omit -Wuninitialized as it’s implied by -Wall. Omit -Wno-address and -Wno-type-limits as they don’t seem to be needed with GCC 14. --- Makefile | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/Makefile b/Makefile index 6b093013..4d2ac1cf 100644 --- a/Makefile +++ b/Makefile @@ -313,7 +313,7 @@ GCC_INSTRUMENT = \ -fsanitize=undefined -fsanitize-address-use-after-scope \ -fsanitize-undefined-trap-on-error -fstack-protector # Omit -fanalyzer from GCC_DEBUG_FLAGS, as it makes GCC too slow. -GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ +GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 \ $(GCC_INSTRUMENT) \ -Wall -Wextra \ -Walloc-size-larger-than=100000 -Warray-bounds=2 \ @@ -332,10 +332,9 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ -Wsuggest-attribute=const -Wsuggest-attribute=format \ -Wsuggest-attribute=malloc \ -Wsuggest-attribute=noreturn -Wsuggest-attribute=pure \ - -Wtrampolines -Wundef -Wuninitialized -Wunused-macros -Wuse-after-free=3 \ + -Wtrampolines -Wundef -Wunused-macros -Wuse-after-free=3 \ -Wvariadic-macros -Wvla -Wwrite-strings \ - -Wno-address -Wno-format-nonliteral -Wno-sign-compare \ - -Wno-type-limits + -Wno-format-nonliteral -Wno-sign-compare # # If your system has a "GMT offset" field in its "struct tm"s # (or if you decide to add such a field in your system's "time.h" file), -- 2.43.0

2 5

Re: [tz] Unicode CLDR supplemental/windowsZones.xml update? -Brooks Harris
by Paul Eggert May 27, 2024

May 27, 2024

On 2024-05-26 12:44, Brooks Harris wrote: > Hi Pail, > On 2024-05-26 03:37 PM, Paul Eggert wrote: >> On 2024-05-26 12:30, Brooks Harris via tz wrote: >>> What is the best procedure to obtain the latest windowsZones.xml? >> >> https://github.com/unicode-org/cldr/blob/main/common/supplemental/windowsZo… > > This file is identical to the old one I have and does not reflect the > commits you referred me to. That's not a file, it's a bunch of info about the file. The info includes the file contents and a bunch of other stuff. If you just want the file, click the Raw button. >>> Is there a record of earlier versions? >> https://github.com/unicode-org/cldr/commits/main/common/supplemental/window… >> >> These are reachable from the earlier URL I emailed. > > Right, but no version of windowsZones.xml I can find has those commits > applied. ? Those changes are visible to me via that URL. Anyway, try clicking the "Raw" button. It should give you this URL: https://raw.githubusercontent.com/unicode-org/cldr/main/common/supplemental… and I see the changes there too.

4 7

[PROPOSED 1/4] Update GCC_DEBUG_FLAGS for GCC 14
by Paul Eggert May 25, 2024

May 25, 2024

* Makefile (GCC_DEBUG_FLAGS): Add -Wflex-array-member-not-at-end, -Wmissing-variable-declarations. --- Makefile | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 3f550b3f..a72fb2ea 100644 --- a/Makefile +++ b/Makefile @@ -315,10 +315,11 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ -Walloc-size-larger-than=100000 -Warray-bounds=2 \ -Wbad-function-cast -Wbidi-chars=any,ucn -Wcast-align=strict -Wdate-time \ -Wdeclaration-after-statement -Wdouble-promotion \ - -Wduplicated-branches -Wduplicated-cond \ + -Wduplicated-branches -Wduplicated-cond -Wflex-array-member-not-at-end \ -Wformat=2 -Wformat-overflow=2 -Wformat-signedness -Wformat-truncation \ -Wimplicit-fallthrough=5 -Winit-self -Wlogical-op \ - -Wmissing-declarations -Wmissing-prototypes -Wnested-externs \ + -Wmissing-declarations -Wmissing-prototypes \ + -Wmissing-variable-declarations -Wnested-externs \ -Wnull-dereference \ -Wold-style-definition -Woverlength-strings -Wpointer-arith \ -Wshadow -Wshift-overflow=2 -Wstrict-overflow \ -- 2.45.1

1 3