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FYI: What do we do? (Six Digit Dates)
by Monty Solomon Aug. 17, 1994

Aug. 17, 1994

Begin forwarded message: Date: Fri, 11 Aug 1994 23:00:58 -0500 (EST) Newsgroups: tdr.problems From: Problem Reporting Service <PROBLEMS(a)tdr.com> Organization: Tansin A. Darcos & Company, Silver Spring MD USA Errors-To: PROBLEM-ERRORS(a)tdr.com Subject: 0026 - Exactly. What do we do? (Six Digit Dates) To: Recipients of list Problems <PROBLEMS(a)tdr.com> Please excuse the long delay between the prior posting and this one, I have been busy with a number of very critical issues unrelated to the posting below. I also didn't want to bother simply raising this issue - it's been raised many times before - and simply offer no solution as everyone else before, because all of them seems to have been unable to offer one before. I've been trying to think of a way to solve the problem. I - and probably many of you - have been trying to figure out what to do about it. I might have *a* solution. At the end of the movie of Dr. Michael Chrichton's "The Andromeda Strain" in a congressional hearing a Senator asks Dr. Stone what they can do if another biological emergency occurs. "What do we do then?" he asks. "Exactly, " responds Dr. Stone, "What do we do?" The problem is the issue of six-digit dates and the turn of the century, now less than six years away. The problem is probably not as bad as it was, because with the introduction of IBM PCs which support dates past the year 2100, the issue isn't a problem except to the extent of programs that still use six-digit dates. Some of you might not understand why this is a serious issue. I'll explain. Much software which is still in use - especially on mainframes - was written ten, fifteen, even twenty years ago for use in the solving of current problems at that time. Some of that software survives, even twenty years later. As I once pointed out in a posting on the newsgroup alt.cobol, a large company might have a massive 2,000,000 line cobol program with 500 modules that requires 50 programmers for its constant maintenance, care and feeding, and that over the years the company has probably spent in excess of fifteen million dollars. These applications are the "bet the company" applications that are used every day to keep it in business. They are the "crown jewels" that if anything goes wrong with the application, the company might actually go into Chapter 11 or suffer massive customer backlash. These applications cannot be rewritten because it would be too expensive, and the company can't afford to be without them. Thus, unless something happens to encourage the company to change its systems, they will continue running these old, maintenance-heavy applications, even five or ten years from now. In some cases, the program is so huge and so complicated nobody knows everything it does; it is beyond the capacity of any one person to know every function and interface and module. Therefore it can't be said with certainty what the different sections are doing with each other. Thus finding where things are happening can be frustratingly difficult. Which comes to the issue at hand. Many of these programs were written to use dates which are six digits in length. Three days from now it will be August 14, 1994. You can write that as 08/14/94 or 14/8/94 depending on which way your system codes dates. (I wanted to avoid confusion, because 8/11 or 11/8 could be referring to August 11 or November 8, but 8/14 or 14/8 as a date cannot be mistaken for anything else.) Figuring out the difference between 8/14/94 and 8/15/94 is no problem, and figuring out that 8/13/95 is after 8/14/94 is also no problem. The last date of this century is Friday, December 31, 1999. 12/31/99. Want to tell me what the next date after that is? Saturday, January 1, 2000. 01/01/00. Which date is earlier, 01/01/99 or 01/03/00? What is the mathematical difference between 12/15/99 and 12/31/99 or between 11/15/99 and 12/02/99? About two weeks. What is the mathematical difference between 12/15/99 and 01/03/00? About 99 years. And think about what that means to anything that uses dates or timing to calculate things that are to happen. Hypothetical Example #1. I use my Visa Card to charge $15.00 on December 15, 1999, and the bill is calculated on Monday, January 3, 2000. 99 years of 21% compounded interest on $15 can be over a billion dollars. Depending on where the minus sign is, either the company is going to think I haven't paid them for 99 years, and freeze my account, send me a bill for $1 billion in interest, or roll over into positive numbers, and tell me my account has $1 billion in available credit. "Hello, British Embassy? I'd like to buy Tristan Da Cunha and set up my own country. I can charge $500,000,000 to my American Express Card." Or it simply dumps every account with outstanding balances for manual handling as the numbers are outrageous, which effectively stops automatic billing. Or the system simply crashes. Scenario #2. A major petrochemical processing plant has a system that cooks a batch of chemicals for a certain period of time, before pushing that load out to the next process. The plant runs continuously, and batches are cooked according to time. A plant computer shoves a load in to cook for one hour beginning at 11:45 pm on December 31, 1999. At Midnight, one of these things happens: (1) the system notices that the batch has been in the oven too long, and pushes a batch of molten chemicals into the next process, where the process of spraying them causes an explosion. (2) the clock counter overflows and shuts down the whole system. (3) the system counter overflows and the batch isn't released, so it overcooks in the oven and perhaps explodes under high heat. (4) the batch stays in the oven while a new batch is shoved in, overloading the oven and causing an explosion. (5) any of these explosions carries back through the utilities and supplies, causing gas line explosions or power surges, as a plant that is eating perhaps 2 megawatts of power suddenly drops off the grid, causing an instant overflow and shutting down power for several areas. Scenario #3. Several power plants go into maintenance shutdown because they've been running continuously for 98 years and 7 months longer than the maximum 90 day operating maximum. Some Nuclear Power plant goes critical or shuts down because the system believes that the rods have been installed too long. So having looked at this issue, what can we do about it? I got thinking about this. In some systems, there's little or no room to expand their data files and the ability to remove running applications is impossible. Therefore any method that changes the system must allow their applications to continue running. And I thought of a method. By coding the date into a character field, effectively in base 32, it would be possible to encode a larger date and still only use 6 characters. By encoding the year to use the letters of the alphabet, e.g. AA through ZZ plus A0 through Z0, it is possible to cover more than 900 years, e.g. start counting with 1400 through 2300, thus covering any date that could have occurred during civilization. In fact, if one wants to encode the month and day - Month encoded to add A,B and C and day encoded as 1-9 and A-V, it is possible to use 4 digits for the year and still fit everything into 6 bytes. Or encode both and fit everything into 4 bytes. This would also then work for places using packed decimal for the six-digit year and thus only allowing 4 bytes. One of the things that is necessary is to make programs expecting numbers fail so that they can be changed, although it would be better to find the programs that use date fields and change them before they crash. Programs that read these records will have to expect both old and new format records, while programs that write them should only output the new format. The point is that with many sites having hundreds or even thousands of programs, the effort could be equivalent to three full-time people over a three year period at some sites. (Some companies have thousands or tens of thousands of programs in their libraries.) This is extra and additional maintenance on top of current maintenance. Expensive overhead that will get worse in the future as it needs to be more urgently done. What is needed are automated searching and checking facilities to find programs that manipulate dates and change those programs to handle a new date format using this compressed date format I have thought of. If we do not make the changes, we could be looking at failed programs, massive errors, disasters and setbacks that could produce serious, perhaps even fatal problems. It can't be done in a hurry in the last 6 months of 1999. Let us not forget the amount of time needed to do updates, which could be days or weeks, depending on how good the automated tools are and how many applications they have. What do we need to do? (1). If your site has inhouse applications, and lots of source files, you need to push for the acquisition of automated checking tools. (2). You need to push for the manpower and resources necessary to do the work now rather than later, because "later" won't be budgeted for. (3). You need to push for the updating of databases to allow full 8-digit dates. (4). Push for all reports to eliminate use of 6-digit dates, even in display fields. (5). Find out what your vendor is doing if you use canned applications. If we work on the problem now while there is time, we can do this with less error and better control, then trying to rush fixes in November of 1999 when errors could spell disaster. If you have better ideas on how to solve the six-digit problem, please write back. ---- To Reply to this message, write to <PROBLEMS(a)TDR.COM>; for private replies or subscriptions use <problems-request(a)tdr.com>; or use newsgroup <tdr.problems>. Please feel free to redistribute this article widely. This message is file ftp.digex.net:/pub/access/tdarcos/0026

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EU Summer Time update
by Peter Ilieve June 8, 1994

June 8, 1994

The European Union bureaucracy has edged a step closer to a 7th Directive on summer-time arrangements. I have the text of a Common Position ((EC No 9/94) and a statement of the Council's reasons dated 4 March 94, reported in the Official Journal of the EC, No. C 137/38--41. Since I reported on the draft directive in March, 1998 has been removed from the scope of the 7th directive and the introduction of a common end date at the end of October has been brought forward to 1996 from 1997. No actual dates have changed. The dates again: Year Start End End (UK & Eire, 1995 only) (rule) (last Sun) (last Sun) (4th Sun) 1995 26 March 24 September 22 October 1996 31 March 27 October 1997 30 March 26 October In the statement of reasons it said the Council had rejected an amendment from the European Parliament relating to having a single timezone for the whole EU, noting that the Commission had said it was beyond the scope of the directive. It still looks unlikely to me that this idea, put forward in the UK from time to time, will ever come to pass. Normally each directive includes a provision that a new directive will be in place on 1 Jan of the last year covered by the preceeding one. This is always ignored, here we are in June and we still don't have the directive promised for January. This Common Position breaks new ground in that it tells the Commission to have proposals ready by 1 Jan 96, so a new directive can be adopted by 1 Jan 97. We will have to wait and see if this makes any difference. I think this is the final step before the directive is adopted but the Edinburgh EC Information Office could still give no guess as to when that might be. Peter Ilieve peter(a)memex.co.uk

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Re: proposed corrections for Russia, Ukraine, Bahamas
by ado June 4, 1994

June 4, 1994

The file ~ftp/pub/tzdata94e.tar.gz on elsie.nci.nih.gov (128.231.16.1) incorporates the proposed changes. --ado

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proposed corrections for Russia, Ukraine, Bahamas
by eggert＠twinsun.com June 3, 1994

June 3, 1994

The letter from "Andy J. Chichak" <chch(a)gateway.tiasur.tomsk.su> about Tomsk prompted me to check the Russian time zone data more carefully. Unfortunately it's a mess, as Shanks was published in 1991, a year that saw chaos in Russian time zones. Though it's hard to know what the correct rules are, it _is_ clear that the rules I submitted last year to the tz database are incorrect, since I got lost with the +1hour -1hour business and ended up omitting a timezone just west of the Urals. Given Chichak's comments about being N hours away from Moscow, I decided that the most likely possibility is that Russia kept in synch with Moscow (for which we already have a detailed post-1991 update from "Andrew A. Chernov" <ache(a)astral.msk.su>). I'd guess also that Belarus followed suit, but (as described below) we know that Ukraine did not, so I'd guess the other western bits of the ex-Soviet Union stuck with EET instead of Moscow time. We have no data on Central Asia and the Caucausus, so I'd guess we should stick with the pre-1991 rules for it until we have more data. The following proposed corrections insert that missing timezone (its biggest city is Kuybyshev) and bump the remaining Russian timezones by one; this gives the proper value for Tomsk and Novosibirsk as reported by Chichak. The latest _Economist_ reports that the Crimea, as part of its attempt to break away from Ukraine, has switched from Kiev time to Moscow time, so I've proposed another timezone entry Europe/Simferopol to take this into account. Also, more people seem to be calling Macedonia ``Macedonia'' instead of the odd ``The Former Yugoslav Republic of Macedonia'' moniker that was first pasted on it, so I think we should call it by its common name. Finally, there is a minor typo in the Bahamas entry. =================================================================== RCS file: RCS/northamerica,v retrieving revision 1994.4 retrieving revision 1994.4.1.1 diff -c -r1994.4 -r1994.4.1.1 *** northamerica 1994/02/07 14:57:50 1994.4 --- northamerica 1994/05/29 04:38:57 1994.4.1.1 *************** *** 629,635 **** # Bahamas # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S ! Rule Bahamas 1912 max - Mar 2 0:00 0 S Rule Bahamas 1964 max - Oct lastSun 2:00 0 S Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D --- 629,635 ---- # Bahamas # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S ! Rule Bahamas 1912 only - Mar 2 0:00 0 S Rule Bahamas 1964 max - Oct lastSun 2:00 0 S Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D =================================================================== RCS file: RCS/asia,v retrieving revision 1994.4 retrieving revision 1994.4.1.1 diff -c -r1994.4 -r1994.4.1.1 *** asia 1994/02/07 14:57:49 1994.4 --- asia 1994/05/29 04:38:57 1994.4.1.1 *************** *** 29,39 **** # 4:00 BSK BSD Baku* # 4:00 GST GDT Gulf* # 4:30 AFT Afghanistan* ! # 5:00 TSK TSD Tashkent* # 5:00 PKT Pakistan* # 5:30 IST IST India # 5:45 NPT Nepal* # 6:00 BGT Bengal, Bangladesh* # 6:30 BMT Burma* # 7:00 ICT Indochina* # 7:00 JVT Java* --- 29,40 ---- # 4:00 BSK BSD Baku* # 4:00 GST GDT Gulf* # 4:30 AFT Afghanistan* ! # 5:00 ASK ASD Ashkhabad* # 5:00 PKT Pakistan* # 5:30 IST IST India # 5:45 NPT Nepal* # 6:00 BGT Bengal, Bangladesh* + # 6:00 TSK TSD Tashkent* # 6:30 BMT Burma* # 7:00 ICT Indochina* # 7:00 JVT Java* *************** *** 60,72 **** ############################################################################### # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Russia 1981 1984 - Apr 1 0:00 1:00 D Rule Russia 1981 1983 - Oct 1 0:00 0 K ! Rule Russia 1984 1990 - Sep lastSun 3:00 0 K ! Rule Russia 1985 1990 - Mar lastSun 2:00 1:00 D ! Rule Russia 1992 max - Sep lastSun 2:00s 0 K ! Rule Russia 1992 max - Mar lastSun 2:00s 1:00 D # Afghanistan # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 61,74 ---- ############################################################################### + # From Paul Eggert <eggert(a)twinsun.com> (May 28, 1994): + # We don't know what happened to the clocks in the Caucausus and the ex-Soviet + # Central Asia after 1990. Until we get more info, stick with the pre-1991 rules. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Russia 1981 1984 - Apr 1 0:00 1:00 D Rule Russia 1981 1983 - Oct 1 0:00 0 K ! Rule Russia 1984 max - Sep lastSun 3:00 0 K ! Rule Russia 1985 max - Mar lastSun 2:00 1:00 D # Afghanistan # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 78,92 **** # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Yerevan 2:58:00 - LMT 1924 May 2 3:00 - MSK 1957 Mar ! 4:00 Russia BS%s 1991 Sep 29 3:00 ! 3:00 Russia MS%s # Azerbaijan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Baku 3:19:24 - LMT 1924 May 2 3:00 - MSK 1957 Mar ! 4:00 Russia BS%s 1991 Sep 29 3:00 ! 3:00 Russia MS%s # Bahrain # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 80,92 ---- # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Yerevan 2:58:00 - LMT 1924 May 2 3:00 - MSK 1957 Mar ! 4:00 Russia BS%s # Azerbaijan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Baku 3:19:24 - LMT 1924 May 2 3:00 - MSK 1957 Mar ! 4:00 Russia BS%s # Bahrain # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 277,284 **** Zone Asia/Tbilisi 2:59:16 - LMT 1880 2:59 - LST 1924 May 2 3:00 - MSK 1957 Mar ! 4:00 Russia BS%s 1991 Sep 29 3:00 ! 3:00 Russia MS%s # India # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 277,283 ---- Zone Asia/Tbilisi 2:59:16 - LMT 1880 2:59 - LST 1924 May 2 3:00 - MSK 1957 Mar ! 4:00 Russia BS%s # India # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 516,523 **** # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Almaty 5:07:48 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s 1991 Sep 29 3:00 ! 5:00 Russia TS%s ############################################################################### --- 515,521 ---- # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Almaty 5:07:48 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s ############################################################################### *************** *** 565,572 **** # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Frunze 4:58:24 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s 1991 Sep 29 3:00 ! 5:00 Russia TS%s # Laos # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 563,569 ---- # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Frunze 4:58:24 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s # Laos # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 755,762 **** # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Dushanbe 4:35:12 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s 1991 Sep 29 3:00 ! 5:00 Russia TS%s # Thailand # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 752,758 ---- # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Dushanbe 4:35:12 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s # Thailand # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 767,775 **** # Turkmenistan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Ashkhabad 3:53:32 - LMT 1924 May 2 ! 4:00 - BSK 1957 Mar ! 5:00 Russia SS%s 1991 Sep 29 3:00 ! 4:00 Russia BS%s # United Arab Emirates # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 763,770 ---- # Turkmenistan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Ashkhabad 3:53:32 - LMT 1924 May 2 ! 4:00 - ASK 1957 Mar ! 5:00 Russia AS%s # United Arab Emirates # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 780,787 **** # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Tashkent 4:37:12 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s 1991 Sep 29 3:00 ! 5:00 Russia TS%s # Vietnam # From Paul Eggert <eggert(a)twinsun.com> (November 18, 1993): --- 775,781 ---- # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Tashkent 4:37:12 - LMT 1924 May 2 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s # Vietnam # From Paul Eggert <eggert(a)twinsun.com> (November 18, 1993): =================================================================== RCS file: RCS/europe,v retrieving revision 1994.4 retrieving revision 1994.4.1.1 diff -c -r1994.4 -r1994.4.1.1 *** europe 1994/02/07 14:57:50 1994.4 --- europe 1994/05/29 04:38:57 1994.4.1.1 *************** *** 32,46 **** # 2:00 EET+DST Eastern Europe # 3:00 MSK MSD Moscow # 3:00 TUR+DST Turkey (no longer used)* ! # 4:00 ESK ESD Yekaterinburg* ! # 5:00 OSK OSD Omsk* ! # 6:00 NSK NSD Novosibirsk ! # 7:00 ISK ISD Irkutsk* ! # 8:00 YSK YSD Yakutsk* ! # 9:00 VSK VSD Vladivostok* ! # 10:00 GSK GSD Magadan* ! # 11:00 PSK PSD Petropavlovsk-Kamchatski* ! # 12:00 ASK ASD Anadyr* # # See the `africa' file for Zone naming conventions. # --- 32,47 ---- # 2:00 EET+DST Eastern Europe # 3:00 MSK MSD Moscow # 3:00 TUR+DST Turkey (no longer used)* ! # 4:00 KSK KSD Kuybyshev* ! # 5:00 ESK ESD Yekaterinburg* ! # 6:00 OSK OSD Omsk* ! # 7:00 NSK NSD Novosibirsk ! # 8:00 ISK ISD Irkutsk* ! # 9:00 YSK YSD Yakutsk* ! # 10:00 VSK VSD Vladivostok* ! # 11:00 GSK GSD Magadan* ! # 12:00 PSK PSD Petropavlovsk-Kamchatski* ! # 13:00 ASK ASD Anadyr* # # See the `africa' file for Zone naming conventions. # *************** *** 421,427 **** # ## <years> is either a single year or a hyphen separated range, with -- # ## also accepted as I use this in TeX a lot. # ## <start date> and <end date> are a digit followed bu a month name. ! # ## It is either an nth Saturday or an explcit date, depending on <flags>. # ## 0 and/or none are used when there is no date, as during 1968--71. # ## <flags> can contain `fixed' to indicate explicit dates and `double' # ## to indicate double summer time dates are present. --- 422,428 ---- # ## <years> is either a single year or a hyphen separated range, with -- # ## also accepted as I use this in TeX a lot. # ## <start date> and <end date> are a digit followed bu a month name. ! # ## It is either an nth Saturday or an explicit date, depending on <flags>. # ## 0 and/or none are used when there is no date, as during 1968--71. # ## <flags> can contain `fixed' to indicate explicit dates and `double' # ## to indicate double summer time dates are present. *************** *** 730,739 **** Rule Russia 1921 only - Oct 1 0:00 0 K Rule Russia 1981 1984 - Apr 1 0:00 1:00 D Rule Russia 1981 1983 - Oct 1 0:00 0 K ! Rule Russia 1984 1990 - Sep lastSun 2:00s 0 K ! Rule Russia 1985 1990 - Mar lastSun 2:00s 1:00 D ! Rule Russia 1992 max - Sep lastSun 2:00s 0 K ! Rule Russia 1992 max - Mar lastSun 2:00s 1:00 D # These are for backward compatibility with older versions. --- 731,738 ---- Rule Russia 1921 only - Oct 1 0:00 0 K Rule Russia 1981 1984 - Apr 1 0:00 1:00 D Rule Russia 1981 1983 - Oct 1 0:00 0 K ! Rule Russia 1984 max - Sep lastSun 2:00s 0 K ! Rule Russia 1985 max - Mar lastSun 2:00s 1:00 D # These are for backward compatibility with older versions. *************** *** 813,820 **** 2:31 Russia LST%s 1919 Jul 1 2:00 3:00 Russia MS%s 1922 Oct 2:00 - EET 1930 Jun 21 ! 3:00 Russia MS%s 1991 Sep 29 3:00 ! 2:00 Russia MS%s # Belgium # Whitman and Shanks disagree; go with Shanks, usually. --- 812,822 ---- 2:31 Russia LST%s 1919 Jul 1 2:00 3:00 Russia MS%s 1922 Oct 2:00 - EET 1930 Jun 21 ! 3:00 Russia MS%s 1991 Mar 31 2:00s ! # From Paul Eggert <eggert(a)twinsun.com> (May 28, 1994): A guess at recent dates: ! 2:00 1:00 "EET DST" 1991 Sep 29 2:00s ! 2:00 - EET 1992 Jan 19 2:00s ! 3:00 Russia MS%s # Belgium # Whitman and Shanks disagree; go with Shanks, usually. *************** *** 966,973 **** 2:00 - EET 1940 Aug 6 3:00 - MSK 1941 Sep 15 1:00 M-Eur MET%s 1944 Sep 22 ! 3:00 Russia MS%s 1989 Mar 26 2:00 ! 2:00 M-Eur MET%s # Finland # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S --- 968,976 ---- 2:00 - EET 1940 Aug 6 3:00 - MSK 1941 Sep 15 1:00 M-Eur MET%s 1944 Sep 22 ! 3:00 Russia MS%s 1989 Mar 26 2:00s ! 2:00 1:00 "EET DST" 1989 Sep 24 2:00s ! 2:00 M-Eur EET%s # Finland # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S *************** *** 1162,1168 **** # to the julian/gregorian calendar) over the period in question. # the winter begins on the Saturday next before St. Luke's day # (old style), or on St. Luke's day, if a Saturday. ! # St. Luke's day ought to be traceable from ecclesiatical sources. "old style" # might be a reference to the Julian calendar as opposed to Gregorian, or it # might mean something else (???). The Gregorian calendar was not introduced # in Iceland until 1700. --- 1165,1171 ---- # to the julian/gregorian calendar) over the period in question. # the winter begins on the Saturday next before St. Luke's day # (old style), or on St. Luke's day, if a Saturday. ! # St. Luke's day ought to be traceable from ecclesiastical sources. "old style" # might be a reference to the Julian calendar as opposed to Gregorian, or it # might mean something else (???). The Gregorian calendar was not introduced # in Iceland until 1700. *************** *** 1260,1267 **** 2:00 - EET 1940 Aug 5 3:00 - MSK 1941 Jul 1:00 M-Eur MET%s 1944 Aug 8 ! 3:00 Russia MS%s 1991 Sep 29 3:00 ! 2:00 M-Eur MET%s # Liechtenstein # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 1263,1271 ---- 2:00 - EET 1940 Aug 5 3:00 - MSK 1941 Jul 1:00 M-Eur MET%s 1944 Aug 8 ! 3:00 Russia MS%s 1991 Mar 31 2:00s ! 2:00 1:00 "EET DST" 1991 Sep 29 2:00s ! 2:00 M-Eur EET%s # Liechtenstein # Zone NAME GMTOFF RULES FORMAT [UNTIL] *************** *** 1280,1287 **** 1:00 - MET 1940 Aug 3 3:00 - MSK 1941 Jun 24 1:00 M-Eur MET%s 1944 Aug ! 3:00 Russia MS%s 1991 Sep 29 3:00 ! 2:00 M-Eur MET%s # Luxembourg # Whitman disagrees with most of these dates in minor ways; go with Shanks. --- 1284,1292 ---- 1:00 - MET 1940 Aug 3 3:00 - MSK 1941 Jun 24 1:00 M-Eur MET%s 1944 Aug ! 3:00 Russia MS%s 1991 Mar 31 2:00s ! 2:00 1:00 "EET DST" 1991 Sep 29 2:00s ! 2:00 M-Eur EET%s # Luxembourg # Whitman disagrees with most of these dates in minor ways; go with Shanks. *************** *** 1319,1325 **** 1:00 Belgium MET%s 1979 Apr 1 2:00 1:00 M-Eur MET%s ! # The Former Yugoslav Republic of Macedonia # They switched from the Julian to the Gregorian calendar on 1918 Mar 18. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Skopje 1:25:44 - LMT 1884 --- 1324,1330 ---- 1:00 Belgium MET%s 1979 Apr 1 2:00 1:00 M-Eur MET%s ! # Macedonia # They switched from the Julian to the Gregorian calendar on 1918 Mar 18. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Skopje 1:25:44 - LMT 1884 *************** *** 1351,1358 **** # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Chisinau 1:55:20 - LMT 1924 May 2 2:00 - EET 1930 Jun 21 ! 3:00 - MSK 1981 Apr ! 3:00 Russia MS%s 1991 Sep 29 2:00s 2:00 M-Eur EET%s # Monaco --- 1356,1363 ---- # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Chisinau 1:55:20 - LMT 1924 May 2 2:00 - EET 1930 Jun 21 ! 3:00 Russia MS%s 1991 Mar 31 2:00s ! 2:00 1:00 "EET DST" 1991 Sep 29 2:00s 2:00 M-Eur EET%s # Monaco *************** *** 1435,1441 **** Rule Poland 1919 only - Apr 15 2:00s 1:00 " DST" # Whitman gives 1944 Nov 30; go with Shanks. Rule Poland 1944 only - Oct 4 2:00 0 - ! # For 1944-1948 Whitman gives the previous day; go with SHanks. Rule Poland 1945 only - Apr 29 0:00 1:00 " DST" Rule Poland 1945 only - Nov 1 0:00 0 - Rule Poland 1946 only - Apr 14 0:00 1:00 " DST" --- 1440,1446 ---- Rule Poland 1919 only - Apr 15 2:00s 1:00 " DST" # Whitman gives 1944 Nov 30; go with Shanks. Rule Poland 1944 only - Oct 4 2:00 0 - ! # For 1944-1948 Whitman gives the previous day; go with Shanks. Rule Poland 1945 only - Apr 29 0:00 1:00 " DST" Rule Poland 1945 only - Nov 1 0:00 0 - Rule Poland 1946 only - Apr 14 0:00 1:00 " DST" *************** *** 1574,1647 **** 2:00 M-Eur EET%s # Russia ! # From Paul Eggert <eggert(a)twinsun.com> (November 18, 1993): # Moscow and Novosibirsk time zone names, and Moscow rules after 1991, # are from Andrew A. Chernov <ache(a)astral.msk.su>. ! # I invented the other time zone names. ! # The rest is from Shanks; it's probably wrong after 1991. ! # We're not sure whether St Petersburg switched in step with Moscow after 1991; ! # it might be a useless name, so we'll comment it out for now. # # From Shanks (1991): # Western Russia switched from the Julian to the Gregorian calendar ! # on 1918 Jan 14. Eatern Russia switched on 1920 Mar 18. # In 1929 the Soviet Union instituted a 5 day week; in 1932 it instituted # a 6 day week; on 1940 Jun 27 it returned to the Gregorian week. # Zone NAME GMTOFF RULES FORMAT [UNTIL] ! #Zone Europe/St_Petersburg 2:30:20 - LMT 1880 ! # 2:01 Russia LST%s 1919 Jul 1 2:00 ! # 3:00 Russia MS%s 1922 Oct ! # 2:00 - EET 1930 Jun 21 ! # 3:00 Russia MS%s 1991 Sep 29 3:00 ! # 2:00 Russia SPS%s ! Zone Europe/Moscow 2:30:20 - LMT 1880 ! 2:31 Russia LST%s 1919 Jul 1 2:00 ! 3:00 Russia MS%s 1922 Oct ! 2:00 - EET 1930 Jun 21 ! 3:00 Russia MS%s 1991 Mar lastSun 2:00s ! 2:00 1:00 "EET DST" 1991 Sep lastSun 2:00s ! 2:00 - EET 1992 Jan 19 2:00s ! 3:00 Russia MS%s ! Zone Asia/Yekaterinburg 4:02:34 - LMT 1924 May 2 ! 4:00 - ESK 1957 Mar ! 5:00 Russia ES%s 1991 Sep 29 3:00 ! 4:00 Russia ES%s ! Zone Asia/Omsk 4:53:36 - LMT 1924 May 2 ! 5:00 - TSK 1957 Mar ! 6:00 Russia TS%s 1991 Sep 29 3:00 ! 5:00 Russia OS%s ! Zone Asia/Novosibirsk 5:31:40 - LMT 1924 May 2 ! 6:00 - NSK 1957 Mar ! 7:00 Russia NS%s 1991 Sep 29 3:00 ! 6:00 Russia NS%s ! Zone Asia/Irkutsk 6:57:20 - LMT 1880 ! 6:57 - LST 1924 May 2 ! 7:00 - ISK 1957 Mar ! 8:00 Russia IS%s 1991 Sep 29 3:00 ! 7:00 Russia IS%s ! Zone Asia/Yakutsk 8:38:40 - LMT 1924 May 2 ! 8:00 - YSK 1957 Mar ! 9:00 Russia YS%s 1991 Sep 29 3:00 ! 8:00 Russia YS%s ! Zone Asia/Vladivostok 8:47:44 - LMT 1880 ! 8:48 - LST 1924 May 2 ! 9:00 - VSK 1957 Mar ! 10:00 Russia VS%s 1991 Sep 29 3:00 ! 9:00 Russia VS%s # MSK is taken; settle for GSK. Zone Asia/Magadan 10:03:12 - LMT 1924 May 2 10:00 - GSK 1957 Mar ! 11:00 Russia GS%s 1991 Sep 29 3:00 ! 10:00 Russia GS%s # This name should be Asia/Petropavlovsk-Kamchatski, but that's too long. Zone Asia/Kamchatka 10:34:36 - LMT 1924 May 2 11:00 - PSK 1957 Mar ! 12:00 Russia PS%s 1991 Sep 29 3:00 ! 11:00 Russia PS%s Zone Asia/Anadyr 11:49:56 - LMT 1924 May 2 12:00 - ASK 1957 Mar ! 13:00 Russia AS%s 1991 Sep 29 3:00 ! 12:00 Russia AS%s # Serbia # They switched from the Julian to the Gregorian calendar on 1918 Mar 18. --- 1579,1669 ---- 2:00 M-Eur EET%s # Russia ! # From Paul Eggert <eggert(a)twinsun.com> (May 28, 1994): # Moscow and Novosibirsk time zone names, and Moscow rules after 1991, # are from Andrew A. Chernov <ache(a)astral.msk.su>. ! # I invented the other time zone names, and (unless otherwise specified) ! # guessed what happened after 1991; the clocks were chaotic, and we know little. ! # The rest is from Shanks. # # From Shanks (1991): # Western Russia switched from the Julian to the Gregorian calendar ! # on 1918 Jan 14. Eastern Russia switched on 1920 Mar 18. # In 1929 the Soviet Union instituted a 5 day week; in 1932 it instituted # a 6 day week; on 1940 Jun 27 it returned to the Gregorian week. # Zone NAME GMTOFF RULES FORMAT [UNTIL] ! Zone Europe/Moscow 2:30:20 - LMT 1880 ! 2:31 Russia LST%s 1919 Jul 1 2:00 ! 3:00 Russia MS%s 1922 Oct ! 2:00 - EET 1930 Jun 21 ! 3:00 Russia MS%s 1991 Mar 31 2:00s ! 2:00 1:00 "EET DST" 1991 Sep 29 2:00s ! 2:00 - EET 1992 Jan 19 2:00s ! 3:00 Russia MS%s ! Zone Europe/Kuybyshev 3:20:36 - LMT 1924 May 2 ! 3:00 - KSK 1957 Mar ! 4:00 Russia KS%s 1991 Mar 31 2:00s ! 3:00 1:00 KSD 1991 Sep 29 2:00s ! 3:00 - KSK 1992 Jan 19 2:00s ! 4:00 Russia KS%s ! Zone Asia/Yekaterinburg 4:02:34 - LMT 1924 May 2 ! 4:00 - SSK 1957 Mar ! 5:00 Russia SS%s 1991 Mar 31 2:00s ! 4:00 1:00 SSD 1991 Sep 29 2:00s ! 4:00 - SSK 1992 Jan 19 2:00s ! 5:00 Russia ES%s # name change from Sverdlovsk ! Zone Asia/Omsk 4:53:36 - LMT 1924 May 2 ! 5:00 - OSK 1957 Mar ! 6:00 Russia OS%s 1991 Mar 31 2:00s ! 5:00 1:00 OSD 1991 Sep 29 2:00s ! 5:00 - OSK 1992 Jan 19 2:00s ! 6:00 Russia OS%s ! Zone Asia/Novosibirsk 5:31:40 - LMT 1924 May 2 ! 6:00 - NSK 1957 Mar ! 7:00 Russia NS%s 1991 Mar 31 2:00s ! 6:00 1:00 NSD 1991 Sep 29 2:00s ! 6:00 - NSK 1992 Jan 19 2:00s ! 7:00 Russia NS%s ! Zone Asia/Irkutsk 6:57:20 - LMT 1880 ! 6:57 - LST 1924 May 2 ! 7:00 - ISK 1957 Mar ! 8:00 Russia IS%s 1991 Mar 31 2:00s ! 7:00 1:00 ISD 1991 Sep 29 2:00s ! 7:00 - ISK 1992 Jan 19 2:00s ! 8:00 Russia IS%s ! Zone Asia/Yakutsk 8:38:40 - LMT 1924 May 2 ! 8:00 - YSK 1957 Mar ! 9:00 Russia YS%s 1991 Mar 31 2:00s ! 8:00 1:00 YSD 1991 Sep 29 2:00s ! 8:00 - YSK 1992 Jan 19 2:00s ! 9:00 Russia YS%s ! Zone Asia/Vladivostok 8:47:44 - LMT 1880 ! 8:48 - LST 1924 May 2 ! 9:00 - VSK 1957 Mar ! 10:00 Russia VS%s 1991 Mar 31 2:00s ! 9:00 1:00 VSD 1991 Sep 29 2:00s ! 9:00 - VSK 1992 Jan 19 2:00s ! 10:00 Russia VS%s # MSK is taken; settle for GSK. Zone Asia/Magadan 10:03:12 - LMT 1924 May 2 10:00 - GSK 1957 Mar ! 11:00 Russia GS%s 1991 Mar 31 2:00s ! 10:00 1:00 GSD 1991 Sep 29 2:00s ! 10:00 - GSK 1992 Jan 19 2:00s ! 11:00 Russia GS%s # This name should be Asia/Petropavlovsk-Kamchatski, but that's too long. Zone Asia/Kamchatka 10:34:36 - LMT 1924 May 2 11:00 - PSK 1957 Mar ! 12:00 Russia PS%s 1991 Mar 31 2:00s ! 11:00 1:00 PSD 1991 Sep 29 2:00s ! 11:00 - PSK 1992 Jan 19 2:00s ! 12:00 Russia PS%s Zone Asia/Anadyr 11:49:56 - LMT 1924 May 2 12:00 - ASK 1957 Mar ! 13:00 Russia AS%s 1991 Mar 31 2:00s ! 12:00 1:00 ASD 1991 Sep 29 2:00s ! 12:00 - ASK 1992 Jan 19 2:00s ! 13:00 Russia AS%s # Serbia # They switched from the Julian to the Gregorian calendar on 1918 Mar 18. *************** *** 1816,1827 **** Rule Ukraine 1921 only - Sep 1 0:00 1:00 " DST" Rule Ukraine 1921 only - Oct 1 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] ! Zone Europe/Kiev 2:02:04 - LMT 1880 2:02 Russia LST%s 1919 Jul 1 2:00 2:02 Ukraine LST%s 1924 May 2 2:00 - EET 1930 Jun 21 3:00 Russia MS%s 1990 Jul 17 2:00 M-Eur EET%s ############################################################################### --- 1838,1861 ---- Rule Ukraine 1921 only - Sep 1 0:00 1:00 " DST" Rule Ukraine 1921 only - Oct 1 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] ! Zone Europe/Kiev 2:02:04 - LMT 1880 2:02 Russia LST%s 1919 Jul 1 2:00 2:02 Ukraine LST%s 1924 May 2 2:00 - EET 1930 Jun 21 3:00 Russia MS%s 1990 Jul 17 2:00 M-Eur EET%s + Zone Europe/Simferopol 2:16:24 - LMT 1880 + 2:08 Russia LST%s 1919 Jul 1 2:00 + 2:08 Ukraine LST%s 1924 May 2 + 2:00 - EET 1930 Jun 21 + 3:00 Russia MS%s 1991 Mar 31 2:00s + 2:00 1:00 "EET DST" 1991 Sep 29 2:00s + # From Paul Eggert <eggert(a)twinsun.com> (May 28, 1994): + # Today's _Economist_ (p 45) reports that Crimea switched + # from Kiev to Moscow time sometime after the January elections. + # For now, we'll guess that there was a 2-hour leap forward on March 27. + 2:00 M-Eur EET%s 1994 Mar 27 2:00s + 3:00 Russia MS%s ###############################################################################

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v28i034: strftime - strftime(3) and date(1) implementation, V6.1, Part01/01
by Monty Solomon May 12, 1994

May 12, 1994

FYI Begin forwarded message: Path: decwrl!vixie!vixie!not-for-mail From: arnold(a)skeeve.atl.ga.us (Arnold Robbins) Newsgroups: comp.sources.unix Subject: v28i034: strftime - strftime(3) and date(1) implementation, V6.1, Part01/01 Date: 11 May 1994 22:11:06 -0700 Organization: Vixie Enterprises Lines: 1303 Sender: vixie(a)vix.com Approved: vixie(a)gw.home.vix.com Nntp-Posting-Host: gw.home.vix.com To: unix-sources(a)pa.dec.com Submitted-By: arnold(a)skeeve.atl.ga.us (Arnold Robbins) Posting-Number: Volume 28, Issue 34 Archive-Name: strftime-6.1/part01 In Volume 27, Issue 207 our moderator writes: >[ this recurring package is the cleanest, nicest date(1) and strftime(3) > i have ever seen, including all free or vendor systems. --vix ] To which I can only say, "gosh, thanks!". I had written: > It seems to be an annual event, something in the circling of the stars > overhead, that requires me to post this, at least once a year. (:-) > > I sincerely hope this will be it (at least 'til next year! :-) Alas, it seems to be an annual event that shortly after posting my package, I also post bug fixes. :-) There are three main fixes here. 1) An update to the date.1 man page to reflect that POSIX.2 is not in draft any more, 2) Yet another fix to the %V code, and 3) Portability enhancements if there is no tm_zone field in the struct tm. Thanks to all who sent mail and helped me track down the ISO 8601 issues. This is strftime 6.1. The package is small enough I'm just reposting the whole thing. Arnold Robbins -- The Basement Computer | Laundry increases Internet: arnold(a)skeeve.ATL.GA.US | exponentially in the UUCP: emory!skeeve!arnold | number of children. Bitnet: Forget it. Get on a real network. | -- Miriam Robbins ------------------------- cut here ------------------------------------ #! /bin/sh echo - 'README' cat << 'EOF' > 'README' Tue May 10 21:43:29 EDT 1994 This package implements the Posix 1003.2 date command, as a wrapper around an extended version of the ANSI strftime(3) library routine. Everything in it is public domain. Arnold Robbins -- The Basement Computer | Laundry increases Internet: arnold(a)skeeve.ATL.GA.US | exponentially in the UUCP: { gatech, emory }!skeeve!arnold | number of children. Bitnet: Forget it. Get on a real network. | -- Miriam Robbins EOF echo - 'Makefile' cat << 'EOF' > 'Makefile' # Makefile for PD date and strftime SRCS= date.c strftime.c OBJS= date.o strftime.o DOCS= date.1 strftime.3 # Uncomment the define of HAVE_TZNAME if your system has the tzname[] array. # Uncomment the define of TM_IN_SYS_TIME if struct tm is in <sys/time.h>. # Uncomment the define of TM_ZONE if your struct tm has the tm_zone field. CFLAGS= -O #-DHAVE_TZNAME #-DTM_IN_SYS_TIME #-DHAVE_TM_ZONE date: $(OBJS) $(CC) $(CFLAGS) $(OBJS) -o $@ date.o: date.c strftime.o: strftime.c EOF echo - 'date.c' cat << 'EOF' > 'date.c' /* * date.c * * Public domain implementation of Posix 1003.2 * date command. Lets strftime() do the dirty work. * * Arnold Robbins * arnold(a)skeeve.atl.ga.us * April, 1991 * * Bug fix courtesy of Chris Ritson (C.R.Ritson(a)newcastle.ac.uk) * February, 1994. */ #include <stdio.h> #include <sys/types.h> #include <time.h> extern char *malloc(); extern size_t strftime(); extern int getopt(); extern int optind; int main(argc, argv) int argc; char **argv; { time_t clock; struct tm *now; int c, size, ret; char *defhow = "%a %b %e %H:%M:%S %Z %Y"; char *howto = defhow; char *buf; while ((c = getopt(argc, argv, "u")) != -1) switch (c) { case 'u': putenv("TZ=GMT0"); break; default: fprintf(stderr, "usage: %s [-u] [+format_str]\n", argv[0]); exit(1); } time(& clock); now = localtime(& clock); if (optind < argc && argv[optind][0] == '+') howto = & argv[optind][1]; size = strlen(howto) * 10; if (size < 26) size = 26; if ((buf = malloc(size)) == NULL) { perror("not enough memory"); exit(1); } ret = strftime(buf, size, howto, now); if (ret != 0) printf("%s\n", buf); else { fprintf(stderr, "conversion failed\n"); exit(1); } exit(0); } EOF echo - 'strftime.c' cat << 'EOF' > 'strftime.c' /* * strftime.c * * Public-domain implementation of ANSI C library routine. * * It's written in old-style C for maximal portability. * However, since I'm used to prototypes, I've included them too. * * If you want stuff in the System V ascftime routine, add the SYSV_EXT define. * For extensions from SunOS, add SUNOS_EXT. * For stuff needed to implement the P1003.2 date command, add POSIX2_DATE. * For VMS dates, add VMS_EXT. * For complete POSIX semantics, add POSIX_SEMANTICS. * * The code for %c, %x, and %X is my best guess as to what's "appropriate". * This version ignores LOCALE information. * It also doesn't worry about multi-byte characters. * So there. * * This file is also shipped with GAWK (GNU Awk), gawk specific bits of * code are included if GAWK is defined. * * Arnold Robbins * January, February, March, 1991 * Updated March, April 1992 * Updated April, 1993 * Updated February, 1994 * Updated May, 1994 * * Fixes from ado(a)elsie.nci.nih.gov * February 1991, May 1992 * Fixes from Tor Lillqvist tml(a)tik.vtt.fi * May, 1993 * Further fixes from ado(a)elsie.nci.nih.gov * February 1994 */ #ifndef GAWK #include <stdio.h> #include <ctype.h> #include <string.h> #include <time.h> #endif #if defined(TM_IN_SYS_TIME) || ! defined(GAWK) #include <sys/types.h> #include <sys/time.h> #endif /* defaults: season to taste */ #define SYSV_EXT 1 /* stuff in System V ascftime routine */ #define SUNOS_EXT 1 /* stuff in SunOS strftime routine */ #define POSIX2_DATE 1 /* stuff in Posix 1003.2 date command */ #define VMS_EXT 1 /* include %v for VMS date format */ #ifndef GAWK #define POSIX_SEMANTICS 1 /* call tzset() if TZ changes */ #endif #if defined(POSIX2_DATE) #if ! defined(SYSV_EXT) #define SYSV_EXT 1 #endif #if ! defined(SUNOS_EXT) #define SUNOS_EXT 1 #endif #endif #if defined(POSIX2_DATE) #define adddecl(stuff) stuff #else #define adddecl(stuff) #endif #undef strchr /* avoid AIX weirdness */ #ifndef __STDC__ #define const /**/ extern void *malloc(); extern void *realloc(); extern void tzset(); extern char *strchr(); extern char *getenv(); static int weeknumber(); adddecl(static int iso8601wknum();) #else extern void *malloc(unsigned count); extern void *realloc(void *ptr, unsigned count); extern void tzset(void); extern char *strchr(const char *str, int ch); extern char *getenv(const char *v); static int weeknumber(const struct tm *timeptr, int firstweekday); adddecl(static int iso8601wknum(const struct tm *timeptr);) #endif #ifdef __GNUC__ #define inline __inline__ #else #define inline /**/ #endif #define range(low, item, hi) max(low, min(item, hi)) #if !defined(OS2) && !defined(MSDOS) && defined(HAVE_TZNAME) extern char *tzname[2]; extern int daylight; #endif /* min --- return minimum of two numbers */ #ifndef __STDC__ static inline int min(a, b) int a, b; #else static inline int min(int a, int b) #endif { return (a < b ? a : b); } /* max --- return maximum of two numbers */ #ifndef __STDC__ static inline int max(a, b) int a, b; #else static inline int max(int a, int b) #endif { return (a > b ? a : b); } /* strftime --- produce formatted time */ #ifndef __STDC__ size_t strftime(s, maxsize, format, timeptr) char *s; size_t maxsize; const char *format; const struct tm *timeptr; #else size_t strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr) #endif { char *endp = s + maxsize; char *start = s; auto char tbuf[100]; int i; static short first = 1; #ifdef POSIX_SEMANTICS static char *savetz = NULL; static int savetzlen = 0; char *tz; #endif /* POSIX_SEMANTICS */ #ifndef HAVE_TM_ZONE extern char *timezone(); struct timeval tv; struct timezone zone; #endif /* HAVE_TM_ZONE */ /* various tables, useful in North America */ static const char *days_a[] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", }; static const char *days_l[] = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", }; static const char *months_a[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", }; static const char *months_l[] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December", }; static const char *ampm[] = { "AM", "PM", }; if (s == NULL || format == NULL || timeptr == NULL || maxsize == 0) return 0; /* quick check if we even need to bother */ if (strchr(format, '%') == NULL && strlen(format) + 1 >= maxsize) return 0; #ifndef POSIX_SEMANTICS if (first) { tzset(); first = 0; } #else /* POSIX_SEMANTICS */ tz = getenv("TZ"); if (first) { if (tz != NULL) { int tzlen = strlen(tz); savetz = (char *) malloc(tzlen + 1); if (savetz != NULL) { savetzlen = tzlen + 1; strcpy(savetz, tz); } } tzset(); first = 0; } /* if we have a saved TZ, and it is different, recapture and reset */ if (tz && savetz && (tz[0] != savetz[0] || strcmp(tz, savetz) != 0)) { i = strlen(tz) + 1; if (i > savetzlen) { savetz = (char *) realloc(savetz, i); if (savetz) { savetzlen = i; strcpy(savetz, tz); } } else strcpy(savetz, tz); tzset(); } #endif /* POSIX_SEMANTICS */ for (; *format && s < endp - 1; format++) { tbuf[0] = '\0'; if (*format != '%') { *s++ = *format; continue; } again: switch (*++format) { case '\0': *s++ = '%'; goto out; case '%': *s++ = '%'; continue; case 'a': /* abbreviated weekday name */ if (timeptr->tm_wday < 0 || timeptr->tm_wday > 6) strcpy(tbuf, "?"); else strcpy(tbuf, days_a[timeptr->tm_wday]); break; case 'A': /* full weekday name */ if (timeptr->tm_wday < 0 || timeptr->tm_wday > 6) strcpy(tbuf, "?"); else strcpy(tbuf, days_l[timeptr->tm_wday]); break; #ifdef SYSV_EXT case 'h': /* abbreviated month name */ #endif case 'b': /* abbreviated month name */ if (timeptr->tm_mon < 0 || timeptr->tm_mon > 11) strcpy(tbuf, "?"); else strcpy(tbuf, months_a[timeptr->tm_mon]); break; case 'B': /* full month name */ if (timeptr->tm_mon < 0 || timeptr->tm_mon > 11) strcpy(tbuf, "?"); else strcpy(tbuf, months_l[timeptr->tm_mon]); break; case 'c': /* appropriate date and time representation */ sprintf(tbuf, "%s %s %2d %02d:%02d:%02d %d", days_a[range(0, timeptr->tm_wday, 6)], months_a[range(0, timeptr->tm_mon, 11)], range(1, timeptr->tm_mday, 31), range(0, timeptr->tm_hour, 23), range(0, timeptr->tm_min, 59), range(0, timeptr->tm_sec, 61), timeptr->tm_year + 1900); break; case 'd': /* day of the month, 01 - 31 */ i = range(1, timeptr->tm_mday, 31); sprintf(tbuf, "%02d", i); break; case 'H': /* hour, 24-hour clock, 00 - 23 */ i = range(0, timeptr->tm_hour, 23); sprintf(tbuf, "%02d", i); break; case 'I': /* hour, 12-hour clock, 01 - 12 */ i = range(0, timeptr->tm_hour, 23); if (i == 0) i = 12; else if (i > 12) i -= 12; sprintf(tbuf, "%02d", i); break; case 'j': /* day of the year, 001 - 366 */ sprintf(tbuf, "%03d", timeptr->tm_yday + 1); break; case 'm': /* month, 01 - 12 */ i = range(0, timeptr->tm_mon, 11); sprintf(tbuf, "%02d", i + 1); break; case 'M': /* minute, 00 - 59 */ i = range(0, timeptr->tm_min, 59); sprintf(tbuf, "%02d", i); break; case 'p': /* am or pm based on 12-hour clock */ i = range(0, timeptr->tm_hour, 23); if (i < 12) strcpy(tbuf, ampm[0]); else strcpy(tbuf, ampm[1]); break; case 'S': /* second, 00 - 61 */ i = range(0, timeptr->tm_sec, 61); sprintf(tbuf, "%02d", i); break; case 'U': /* week of year, Sunday is first day of week */ sprintf(tbuf, "%02d", weeknumber(timeptr, 0)); break; case 'w': /* weekday, Sunday == 0, 0 - 6 */ i = range(0, timeptr->tm_wday, 6); sprintf(tbuf, "%d", i); break; case 'W': /* week of year, Monday is first day of week */ sprintf(tbuf, "%02d", weeknumber(timeptr, 1)); break; case 'x': /* appropriate date representation */ sprintf(tbuf, "%s %s %2d %d", days_a[range(0, timeptr->tm_wday, 6)], months_a[range(0, timeptr->tm_mon, 11)], range(1, timeptr->tm_mday, 31), timeptr->tm_year + 1900); break; case 'X': /* appropriate time representation */ sprintf(tbuf, "%02d:%02d:%02d", range(0, timeptr->tm_hour, 23), range(0, timeptr->tm_min, 59), range(0, timeptr->tm_sec, 61)); break; case 'y': /* year without a century, 00 - 99 */ i = timeptr->tm_year % 100; sprintf(tbuf, "%02d", i); break; case 'Y': /* year with century */ sprintf(tbuf, "%d", 1900 + timeptr->tm_year); break; case 'Z': /* time zone name or abbrevation */ #ifdef HAVE_TZNAME i = (daylight && timeptr->tm_isdst); /* 0 or 1 */ strcpy(tbuf, tzname[i]); #else #ifdef HAVE_TM_ZONE strcpy(tbuf, timeptr->tm_zone); #else gettimeofday(& tv, & zone); strcpy(tbuf, timezone(zone.tz_minuteswest, timeptr->tm_isdst)); #endif #endif break; #ifdef SYSV_EXT case 'n': /* same as \n */ tbuf[0] = '\n'; tbuf[1] = '\0'; break; case 't': /* same as \t */ tbuf[0] = '\t'; tbuf[1] = '\0'; break; case 'D': /* date as %m/%d/%y */ strftime(tbuf, sizeof tbuf, "%m/%d/%y", timeptr); break; case 'e': /* day of month, blank padded */ sprintf(tbuf, "%2d", range(1, timeptr->tm_mday, 31)); break; case 'r': /* time as %I:%M:%S %p */ strftime(tbuf, sizeof tbuf, "%I:%M:%S %p", timeptr); break; case 'R': /* time as %H:%M */ strftime(tbuf, sizeof tbuf, "%H:%M", timeptr); break; case 'T': /* time as %H:%M:%S */ strftime(tbuf, sizeof tbuf, "%H:%M:%S", timeptr); break; #endif #ifdef SUNOS_EXT case 'k': /* hour, 24-hour clock, blank pad */ sprintf(tbuf, "%2d", range(0, timeptr->tm_hour, 23)); break; case 'l': /* hour, 12-hour clock, 1 - 12, blank pad */ i = range(0, timeptr->tm_hour, 23); if (i == 0) i = 12; else if (i > 12) i -= 12; sprintf(tbuf, "%2d", i); break; #endif #ifdef VMS_EXT case 'v': /* date as dd-bbb-YYYY */ sprintf(tbuf, "%02d-%3.3s-%4d", range(1, timeptr->tm_mday, 31), months_a[range(0, timeptr->tm_mon, 11)], timeptr->tm_year + 1900); for (i = 3; i < 6; i++) if (islower(tbuf[i])) tbuf[i] = toupper(tbuf[i]); break; #endif #ifdef POSIX2_DATE case 'C': sprintf(tbuf, "%02d", (timeptr->tm_year + 1900) / 100); break; case 'E': case 'O': /* POSIX locale extensions, ignored for now */ goto again; case 'V': /* week of year according ISO 8601 */ #if defined(GAWK) && defined(VMS_EXT) { extern int do_lint; extern void warning(); static int warned = 0; if (! warned && do_lint) { warned = 1; warning( "conversion %%V added in P1003.2; for VMS style date, use %%v"); } } #endif sprintf(tbuf, "%02d", iso8601wknum(timeptr)); break; case 'u': /* ISO 8601: Weekday as a decimal number [1 (Monday) - 7] */ sprintf(tbuf, "%d", timeptr->tm_wday == 0 ? 7 : timeptr->tm_wday); break; #endif /* POSIX2_DATE */ default: tbuf[0] = '%'; tbuf[1] = *format; tbuf[2] = '\0'; break; } i = strlen(tbuf); if (i) { if (s + i < endp - 1) { strcpy(s, tbuf); s += i; } else return 0; } } out: if (s < endp && *format == '\0') { *s = '\0'; return (s - start); } else return 0; } /* isleap --- is a year a leap year? */ #ifndef __STDC__ static int isleap(year) int year; #else static int isleap(int year) #endif { return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0); } #ifdef POSIX2_DATE /* iso8601wknum --- compute week number according to ISO 8601 */ #ifndef __STDC__ static int iso8601wknum(timeptr) const struct tm *timeptr; #else static int iso8601wknum(const struct tm *timeptr) #endif { /* * From 1003.2: * If the week (Monday to Sunday) containing January 1 * has four or more days in the new year, then it is week 1; * otherwise it is the highest numbered week of the previous * (52 or 53) year, and the next week is week 1. * * ADR: This means if Jan 1 was Monday through Thursday, * it was week 1, otherwise week 52 or 53. * * XPG4 erroneously included POSIX.2 rationale text in the * main body of the standard. Thus it requires week 53. */ int weeknum, jan1day, diff; /* get week number, Monday as first day of the week */ weeknum = weeknumber(timeptr, 1); /* * With thanks and tip of the hatlo to tml(a)tik.vtt.fi * * What day of the week does January 1 fall on? * We know that * (timeptr->tm_yday - jan1.tm_yday) MOD 7 == * (timeptr->tm_wday - jan1.tm_wday) MOD 7 * and that * jan1.tm_yday == 0 * and that * timeptr->tm_wday MOD 7 == timeptr->tm_wday * from which it follows that. . . */ jan1day = timeptr->tm_wday - (timeptr->tm_yday % 7); if (jan1day < 0) jan1day += 7; /* * If Jan 1 was a Monday through Thursday, it was in * week 1. Otherwise it was last year's highest week, which is * this year's week 0. * * What does that mean? * If Jan 1 was Monday, the week number is exactly right, it can * never be 0. * If it was Tuesday through Thursday, the weeknumber is one * less than it should be, so we add one. * Otherwise, Friday, Saturday or Sunday, the week number is * OK, but if it is 0, it needs to be 52 or 53. */ switch (jan1day) { case 1: /* Monday */ break; case 2: /* Tuesday */ case 3: /* Wednedsday */ case 4: /* Thursday */ weeknum++; break; case 5: /* Friday */ case 6: /* Saturday */ case 0: /* Sunday */ if (weeknum == 0) { #ifdef USE_BROKEN_XPG4 /* XPG4 (as of March 1994) says 53 unconditionally */ weeknum = 53; #else /* get week number of last week of last year */ struct tm dec31ly; /* 12/31 last year */ dec31ly = *timeptr; dec31ly.tm_year--; dec31ly.tm_mon = 11; dec31ly.tm_mday = 31; dec31ly.tm_wday = (jan1day == 0) ? 6 : jan1day - 1; dec31ly.tm_yday = 364 + isleap(dec31ly.tm_year + 1900); weeknum = iso8601wknum(& dec31ly); #endif } break; } return weeknum; } #endif /* weeknumber --- figure how many weeks into the year */ /* With thanks and tip of the hatlo to ado(a)elsie.nci.nih.gov */ #ifndef __STDC__ static int weeknumber(timeptr, firstweekday) const struct tm *timeptr; int firstweekday; #else static int weeknumber(const struct tm *timeptr, int firstweekday) #endif { int wday = timeptr->tm_wday; int ret; if (firstweekday == 1) { if (wday == 0) /* sunday */ wday = 6; else wday--; } ret = ((timeptr->tm_yday + 7 - wday) / 7); if (ret < 0) ret = 0; return ret; } #if 0 /* ADR --- I'm loathe to mess with ado's code ... */ Date: Wed, 24 Apr 91 20:54:08 MDT From: Michal Jaegermann <audfax!emory!vm.ucs.UAlberta.CA!NTOMCZAK> To: arnold(a)audiofax.com Hi Arnold, in a process of fixing of strftime() in libraries on Atari ST I grabbed some pieces of code from your own strftime. When doing that it came to mind that your weeknumber() function compiles a little bit nicer in the following form: /* * firstweekday is 0 if starting in Sunday, non-zero if in Monday */ { return (timeptr->tm_yday - timeptr->tm_wday + (firstweekday ? (timeptr->tm_wday ? 8 : 1) : 7)) / 7; } How nicer it depends on a compiler, of course, but always a tiny bit. Cheers, Michal ntomczak(a)vm.ucs.ualberta.ca #endif #ifdef TEST_STRFTIME /* * NAME: * tst * * SYNOPSIS: * tst * * DESCRIPTION: * "tst" is a test driver for the function "strftime". * * OPTIONS: * None. * * AUTHOR: * Karl Vogel * Control Data Systems, Inc. * vogelke(a)c-17igp.wpafb.af.mil * * BUGS: * None noticed yet. * * COMPILE: * cc -o tst -DTEST_STRFTIME strftime.c */ /* ADR: I reformatted this to my liking, and deleted some unneeded code. */ #ifndef NULL #include <stdio.h> #endif #include <sys/time.h> #include <string.h> #define MAXTIME 132 /* * Array of time formats. */ static char *array[] = { "(%%A) full weekday name, var length (Sunday..Saturday) %A", "(%%B) full month name, var length (January..December) %B", "(%%C) Century %C", "(%%D) date (%%m/%%d/%%y) %D", "(%%E) Locale extensions (ignored) %E", "(%%H) hour (24-hour clock, 00..23) %H", "(%%I) hour (12-hour clock, 01..12) %I", "(%%M) minute (00..59) %M", "(%%O) Locale extensions (ignored) %O", "(%%R) time, 24-hour (%%H:%%M) %R", "(%%S) second (00..61) %S", "(%%T) time, 24-hour (%%H:%%M:%%S) %T", "(%%U) week of year, Sunday as first day of week (00..53) %U", "(%%V) week of year according to ISO 8601 %V", "(%%W) week of year, Monday as first day of week (00..53) %W", "(%%X) appropriate locale time representation (%H:%M:%S) %X", "(%%Y) year with century (1970...) %Y", "(%%Z) timezone (EDT), or blank if timezone not determinable %Z", "(%%a) locale's abbreviated weekday name (Sun..Sat) %a", "(%%b) locale's abbreviated month name (Jan..Dec) %b", "(%%c) full date (Sat Nov 4 12:02:33 1989)%n%t%t%t %c", "(%%d) day of the month (01..31) %d", "(%%e) day of the month, blank-padded ( 1..31) %e", "(%%h) should be same as (%%b) %h", "(%%j) day of the year (001..366) %j", "(%%k) hour, 24-hour clock, blank pad ( 0..23) %k", "(%%l) hour, 12-hour clock, blank pad ( 0..12) %l", "(%%m) month (01..12) %m", "(%%p) locale's AM or PM based on 12-hour clock %p", "(%%r) time, 12-hour (same as %%I:%%M:%%S %%p) %r", "(%%u) ISO 8601: Weekday as decimal number [1 (Monday) - 7] %u", "(%%v) VAX date (dd-bbb-YYYY) %v", "(%%w) day of week (0..6, Sunday == 0) %w", "(%%x) appropriate locale date representation %x", "(%%y) last two digits of year (00..99) %y", (char *) NULL }; /* main routine. */ int main(argc, argv) int argc; char **argv; { long time(); char *next; char string[MAXTIME]; int k; int length; struct tm *tm; long clock; /* Call the function. */ clock = time((long *) 0); tm = localtime(&clock); for (k = 0; next = array[k]; k++) { length = strftime(string, MAXTIME, next, tm); printf("%s\n", string); } exit(0); } #endif /* TEST_STRFTIME */ EOF echo - 'date.1' cat << 'EOF' > 'date.1' .TH DATE 1 .SH NAME date \- write the date and time .SH SYNOPSIS .B date [ .B \-u ] [ .RI + format ] .SH DESCRIPTION .I Date writes the current date and time to the standard output. It is intended to be compliant with the Posix 1003.2 Command Language and Utilities standard. Therefore, it is purposely .I not usable by the super-user for setting the system time. .LP .I Date accepts one option: .TP .B \-u Perform operations as if the .B TZ environment variable was set to .BR GMT0 . .LP If an argument to .I date is given that begins with a ``+'', then the output is controlled by the contents of the rest of the string. Normal text is output unmodified, while field descriptors in the format string are substituted for. .LP The .I date program is essentially a wrapper around .IR strftime (3); see there for a description of the available formatting options. .LP If no format string is given, or if it does not begin with a ``+'', then the default format of \fB"%a %b %e %H:%M:%S %Z %Y"\fR will be used. This produces the traditional style of output, such as ``Sun Mar 17 10:32:47 EST 1991''. .SH SEE ALSO time(2), strftime(3), localtime(3) .SH BUGS This version only works for the POSIX locale. .SH AUTHOR .nf Arnold Robbins .sp INTERNET: arnold(a)skeeve.atl.ga.us UUCP: emory!skeeve!arnold Phone: +1 404 248 9324 .fi EOF echo - 'strftime.3' cat << 'EOF' > 'strftime.3' .TH STRFTIME 3 .SH NAME strftime \- generate formatted time information .SH SYNOPSIS .ft B .nf #include <sys/types.h> #include <time.h> .sp size_t strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr); .SH DESCRIPTION The following description is transcribed verbatim from the December 7, 1988 draft standard for ANSI C. This draft is essentially identical in technical content to the final version of the standard. .LP The .B strftime function places characters into the array pointed to by .B s as controlled by the string pointed to by .BR format . The format shall be a multibyte character sequence, beginning and ending in its initial shift state. The .B format string consists of zero or more conversion specifiers and ordinary multibyte characters. A conversion specifier consists of a .B % character followed by a character that determines the behavior of the conversion specifier. All ordinary multibyte characters (including the terminating null character) are copied unchanged into the array. If copying takes place between objects that overlap the behavior is undefined. No more than .B maxsize characters are placed into the array. Each conversion specifier is replaced by appropriate characters as described in the following list. The appropriate characters are determined by the .B LC_TIME category of the current locale and by the values contained in the structure pointed to by .BR timeptr . .TP .B %a is replaced by the locale's abbreviated weekday name. .TP .B %A is replaced by the locale's full weekday name. .TP .B %b is replaced by the locale's abbreviated month name. .TP .B %B is replaced by the locale's full month name. .TP .B %c is replaced by the locale's appropriate date and time representation. .TP .B %d is replaced by the day of the month as a decimal number .RB ( 01 - 31 ). .TP .B %H is replaced by the hour (24-hour clock) as a decimal number .RB ( 00 - 23 ). .TP .B %I is replaced by the hour (12-hour clock) as a decimal number .RB ( 01 - 12 ). .TP .B %j is replaced by the day of the year as a decimal number .RB ( 001 - 366 ). .TP .B %m is replaced by the month as a decimal number .RB ( 01 - 12 ). .TP .B %M is replaced by the minute as a decimal number .RB ( 00 - 59 ). .TP .B %p is replaced by the locale's equivalent of the AM/PM designations associated with a 12-hour clock. .TP .B %S is replaced by the second as a decimal number .RB ( 00 - 61 ). .TP .B %U is replaced by the week number of the year (the first Sunday as the first day of week 1) as a decimal number .RB ( 00 - 53 ). .TP .B %w is replaced by the weekday as a decimal number .RB [ "0 " (Sunday)- 6 ]. .TP .B %W is replaced by the week number of the year (the first Monday as the first day of week 1) as a decimal number .RB ( 00 - 53 ). .TP .B %x is replaced by the locale's appropriate date representation. .TP .B %X is replaced by the locale's appropriate time representation. .TP .B %y is replaced by the year without century as a decimal number .RB ( 00 - 99 ). .TP .B %Y is replaced by the year with century as a decimal number. .TP .B %Z is replaced by the time zone name or abbreviation, or by no characters if no time zone is determinable. .TP .B %% is replaced by .BR % . .LP If a conversion specifier is not one of the above, the behavior is undefined. .SH RETURNS If the total number of resulting characters including the terminating null character is not more than .BR maxsize , the .B strftime function returns the number of characters placed into the array pointed to by .B s not including the terminating null character. Otherwise, zero is returned and the contents of the array are indeterminate. .SH NON-ANSI EXTENSIONS If .B SYSV_EXT is defined when the routine is compiled, then the following additional conversions will be available. These are borrowed from the System V .IR cftime (3) and .IR ascftime (3) routines. .TP .B %D is equivalent to specifying .BR %m/%d/%y . .TP .B %e is replaced by the day of the month, padded with a blank if it is only one digit. .TP .B %h is equivalent to .BR %b , above. .TP .B %n is replaced with a newline character (\s-1ASCII LF\s+1). .TP .B %r is equivalent to specifying .BR "%I:%M:%S %p" . .TP .B %R is equivalent to specifying .BR %H:%M . .TP .B %T is equivalent to specifying .BR %H:%M:%S . .TP .B %t is replaced with a \s-1TAB\s+1 character. .PP If .B SUNOS_EXT is defined when the routine is compiled, then the following additional conversions will be available. These are borrowed from the SunOS version of .IR strftime . .TP .B %k is replaced by the hour (24-hour clock) as a decimal number .RB ( 0 - 23 ). Single digit numbers are padded with a blank. .TP .B %l is replaced by the hour (12-hour clock) as a decimal number .RB ( 1 - 12 ). Single digit numbers are padded with a blank. .SH POSIX 1003.2 EXTENSIONS If .B POSIX2_DATE is defined, then all of the conversions available with .B SYSV_EXT and .B SUNOS_EXT are available, as well as the following additional conversions: .TP .B %C The century, as a number between 00 and 99. .TP .B %u is replaced by the weekday as a decimal number .RB [ "1 " (Monday)- 7 ]. .TP .B %V is replaced by the week number of the year (the first Monday as the first day of week 1) as a decimal number .RB ( 01 - 53 ). The method for determining the week number is as specified by ISO 8601 (to wit: if the week containing January 1 has four or more days in the new year, then it is week 1, otherwise it is the highest numbered week of the previous year (52 or 53) and the next week is week 1). .LP The text of the POSIX standard for the .I date utility describes .B %U and .B %W this way: .TP .B %U is replaced by the week number of the year (the first Sunday as the first day of week 1) as a decimal number .RB ( 00 - 53 ). All days in a new year preceding the first Sunday are considered to be in week 0. .TP .B %W is replaced by the week number of the year (the first Monday as the first day of week 1) as a decimal number .RB ( 00 - 53 ). All days in a new year preceding the first Monday are considered to be in week 0. .LP In addition, the alternate representations .BR %Ec , .BR %EC , .BR %Ex , .BR %Ey , .BR %EY , .BR %Od , .BR %Oe , .BR %OH , .BR %OI , .BR %Om , .BR %OM , .BR %OS , .BR %Ou , .BR %OU , .BR %OV , .BR %Ow , .BR %OW , and .B %Oy are recognized, but their normal representations are used. .SH VMS EXTENSIONS If .B VMS_EXT is defined, then the following additional conversion is available: .TP .B %v The date in VMS format (e.g. 20-JUN-1991). .SH SEE ALSO .IR time (2), .IR ctime (3), .IR localtime (3), .IR tzset (3) .SH BUGS This version does not handle multibyte characters or pay attention to the setting of the .B LC_TIME environment variable. .LP It is not clear what is ``appropriate'' for the C locale; the values returned are a best guess on the author's part. .SH CAVEATS The pre-processor symbol .B POSIX_SEMANTICS is automatically defined, which forces the code to call .IR tzset (3) whenever the .B TZ environment variable has changed. If this routine will be used in an application that will not be changing .BR TZ , then there may be some performance improvements by not defining .BR POSIX_SEMANTICS . .SH AUTHOR .nf Arnold Robbins .sp INTERNET: arnold(a)skeeve.atl.ga.us UUCP: emory!skeeve!arnold Phone: +1 404 248 9324 .fi .SH ACKNOWLEDGEMENTS Thanks to Geoff Clare <gwc(a)root.co.uk> for helping debug earlier versions of this routine, and for advice about POSIX semantics. Additional thanks to Arthur David Olsen <ado(a)elsie.nci.nih.gov> for some code improvements. Thanks also to Tor Lillqvist <tml(a)tik.vtt.fi> for code fixes to the ISO 8601 code. EOF

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Re: workaround for common programming error involving ctime and localtime
by ado May 11, 1994

May 11, 1994

> ! /* > ! ** The following is equivalent to `return asctime(localtime(timep));', > ! ** except it does not modify localtime's static storage, > ! ** and thus it works around all-too-common bugs like > ! ** `struct tm *p = localtime(&t1); puts(ctime(&t2)); return p->tm_year'. > ! */ Hmmm...given the X3J11 description of ctime in section 4.12.3.2... The ctime funciton converts the calendar time pointed to by timer to local time in the form of a string. It is equivalent to asctime(localtime(timer)) ...do we open ourselves up to standard conformance challenges if ctime is anything except "asctime(localtime(timer))"? --ado

2 1

support for ICL extension to Posix TZ string parsing
by yata!eggert＠twinsun.com May 8, 1994

May 8, 1994

The following Usenet article describes a extension to Posix TZ strings that allows the strings to express the daylight savings time rules currently used in Britain. At the end of this message is a patch to the tz package that adds support for this extension. This patch also fixes a theoretical leap second problem with Posix TZ strings. But looking at the code, I suspect that leap seconds don't work at all with Posix TZ strings; perhaps this is intentional? Newsgroups: comp.unix.unixware From: jjf(a)dsbc.icl.co.uk (J J Farrell) Subject: Re: Daylight saving time in UW1.1 Message-ID: <CpCvnG.7Dy(a)dsbc.icl.co.uk> Organization: International Computers Limited References: <767043120.AA04204(a)cswamp.apana.org.au> <Cp9x6n.7uB(a)novell.co.uk> Date: Fri, 6 May 1994 00:50:03 GMT In article <Cp9x6n.7uB(a)novell.co.uk> msohnius(a)novell.co.uk (Martin Sohnius) writes: > UnixWare supports two different styles of timezone handling. > > One is what I may call "System V" style, with the TZ environment > variable as described in environ(5). It might be better described as "Standard" style - it's been specified by X/Open for many years, and I think Posix is the same. > Note also that the October rule for many parts of Australia > ("next-to-last Sunday in October") cannot be implemented with the > "System V" style TZ. (NB nor can the British rule, > "day after 4th Saturday in October"). I'm not sure about the Australian ones, but the British rule can be done in "System V" style TZ. The following works on SVR4 systems and has been issued by ICL for several years: GMT0BST,M3.5.0/1,M10.4.6/26 I've not looked up the wording in the SVR4 documentation, but this does break the wording in XPG3; they may have loosened the wording in XPG4, but I haven't checked. It is probably a bug that this works, but bugs can sometimes be useful! My opinions; I do not speak for my employer. =================================================================== RCS file: RCS/localtime.c,v retrieving revision 1994.6.1.2 retrieving revision 1994.6.1.3 diff -c -r1994.6.1.2 -r1994.6.1.3 *** localtime.c 1994/05/09 10:16:11 1994.6.1.2 --- localtime.c 1994/05/09 10:22:51 1994.6.1.3 *************** *** 414,423 **** { int num; ! strp = getnum(strp, &num, 0, HOURSPERDAY); if (strp == NULL) return NULL; ! *secsp = num * SECSPERHOUR; if (*strp == ':') { ++strp; strp = getnum(strp, &num, 0, MINSPERHOUR - 1); --- 414,429 ---- { int num; ! /* ! ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like ! ** "M10.4.6/26", which does not conform to Posix, ! ** but which specifies the equivalent of ! ** ``02:00 on the first Sunday on or after 23 Oct''. ! */ ! strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); if (strp == NULL) return NULL; ! *secsp = num * (long) SECSPERHOUR; if (*strp == ':') { ++strp; strp = getnum(strp, &num, 0, MINSPERHOUR - 1); *************** *** 426,432 **** *secsp += num * SECSPERMIN; if (*strp == ':') { ++strp; ! strp = getnum(strp, &num, 0, SECSPERMIN - 1); if (strp == NULL) return NULL; *secsp += num; --- 432,439 ---- *secsp += num * SECSPERMIN; if (*strp == ':') { ++strp; ! /* `SECSPERMIN' allows for leap seconds. */ ! strp = getnum(strp, &num, 0, SECSPERMIN); if (strp == NULL) return NULL; *secsp += num;

1 0

workaround for common programming error involving ctime and localtime
by yata!eggert＠twinsun.com May 8, 1994

May 8, 1994

The following patch lets the tz package work around a common programming error when using ctime and localtime. =================================================================== RCS file: RCS/localtime.c,v retrieving revision 1994.6.1.1 retrieving revision 1994.6.1.2 diff -c -r1994.6.1.1 -r1994.6.1.2 *** localtime.c 1994/05/05 16:24:49 1994.6.1.1 --- localtime.c 1994/05/09 10:16:11 1994.6.1.2 *************** *** 1136,1142 **** ctime(timep) const time_t * const timep; { ! return asctime(localtime(timep)); } /* --- 1136,1151 ---- ctime(timep) const time_t * const timep; { ! struct tm tm; ! ! /* ! ** The following is equivalent to `return asctime(localtime(timep));', ! ** except it does not modify localtime's static storage, ! ** and thus it works around all-too-common bugs like ! ** `struct tm *p = localtime(&t1); puts(ctime(&t2)); return p->tm_year'. ! */ ! localsub(timep, 0L, &tm); ! return asctime(&tm); } /*

1 0

support for locales
by yata!eggert＠twinsun.com May 8, 1994

May 8, 1994

Here is a patch that adds support for locales to the tz package's strftime function and date command. For example, if the LC_TIME environment variable is set to "de", `date' will output something like `Montag, 9. Mai 1994, 02:59:54 Uhr PDT' instead of the usual `Mon May 9 02:59:54 PDT 1994'. The locale files are in /usr/lib/locale, using the same format as in Solaris 2.3 (which I assume is fairly standard, at least among SVR4-ish hosts). If locale files are absent or are not of the proper form, traditional behavior is assumed. I invented a strftime format `%+', which expands to the default format used by `date'; this makes it easier to put all the locale-relevant stuff in strftime.c, and also lets the user type fun commands like `date "+|%+|"'. This patch also extends strftime to use the format "%c" if its format argument is (char*)0; this is the documented behavior in Solaris 2.3. This patch assumes the Posix/GCC cleanup patch I sent a while back. =================================================================== RCS file: RCS/Makefile,v retrieving revision 1994.7.1.1 retrieving revision 1994.7.1.2 diff -c -r1994.7.1.1 -r1994.7.1.2 *** Makefile 1994/05/05 19:10:21 1994.7.1.1 --- Makefile 1994/05/09 09:47:26 1994.7.1.2 *************** *** 82,87 **** --- 82,88 ---- # -DHAVE_ADJTIME=0 if `adjtime' does not exist (SVR0?) # -DHAVE_LONG_DOUBLE if your compiler supports the `long double' type # -DHAVE_MKDIR=0 if the mkdir system call does not work (SVR0?) + # -DHAVE_SETLOCALE=0 if the setlocale function does not work (SVR3) # -DHAVE_SETTIMEOFDAY=0 if settimeofday does not exist (SVR0?) # -DHAVE_SETTIMEOFDAY=1 if settimeofday has just 1 arg (SVR4) # -DHAVE_SETTIMEOFDAY=2 if settimeofday uses 2nd arg (4.3BSD) *************** *** 89,94 **** --- 90,96 ---- # -DHAVE_STDLIB_H=0 if `#include <stdlib.h>' does not work # -DHAVE_UMASK=0 if `umask(0)' does not work # -DHAVE_UNISTD=0 if `#include <unistd.h>' does not work + # -DLOCALE_HOME=\"path\" if locales are in "path", not "/usr/lib/locale" # -DNEED_STRCHR_DECL=1 if <string.h> does not declare strchr fully # -DNEED_TIME_DECL=1 if <time.h> does not declare `time' fully # -Dalloc_size_t=T if the malloc size argument is of type T, not size_t =================================================================== RCS file: RCS/date.1,v retrieving revision 1994.7 retrieving revision 1994.7.1.1 diff -c -r1994.7 -r1994.7.1.1 *** date.1 1992/11/04 18:08:06 1994.7 --- date.1 1994/05/09 09:47:50 1994.7.1.1 *************** *** 37,42 **** --- 37,43 ---- (or by the abbreviation for the time zone specified in the .B TZ environment variable if set). + The exact output format depends on the locale. .PP If a command-line argument starts with a plus sign .RB (` + '), *************** *** 51,70 **** to be output in a particular way (or identify a special character to output): .nf .if t .in +.5i .if n .in +2 ! .ta \w'%M\0\0'u +\w'Wed Mar 8 14:54:40 1989\0\0'u Sample output Explanation ! %a Wed Abbreviated weekday name ! %A Wednesday Full weekday name ! %b Mar Abbreviated month name ! %B March Full month name ! %c 03/08/89 14:54:40 Month/day/year Hour:minute:second ! %C Wed Mar 8 14:54:40 1989 a la \fIasctime\^\fP(3) %d 08 Day of month (always two digits) %D 03/08/89 Month/day/year (eight characters) %e 8 Day of month (leading zero blanked) ! %h Mar Abbreviated month name %H 14 24-hour-clock hour (two digits) %I 02 12-hour-clock hour (two digits) %j 067 Julian day number (three digits) --- 52,72 ---- to be output in a particular way (or identify a special character to output): .nf + .sp .if t .in +.5i .if n .in +2 ! .ta \w'%M\0\0'u +\w'Wed Mar 8 14:54:40 EST 1989\0\0'u Sample output Explanation ! %a Wed Abbreviated weekday name* ! %A Wednesday Full weekday name* ! %b Mar Abbreviated month name* ! %B March Full month name* ! %c Wed Mar 08 14:54:40 1989 Date and time* ! %C 19 Century %d 08 Day of month (always two digits) %D 03/08/89 Month/day/year (eight characters) %e 8 Day of month (leading zero blanked) ! %h Mar Abbreviated month name* %H 14 24-hour-clock hour (two digits) %I 02 12-hour-clock hour (two digits) %j 067 Julian day number (three digits) *************** *** 82,94 **** %U 10 Sunday-based week number (two digits) %w 3 Day number (one digit, Sunday is 0) %W 10 Monday-based week number (two digits) ! %x 03/08/89 Month/day/year (eight characters) ! %X 14:54:40 Hour:minute:second %y 89 Last two digits of year %Y 1989 Year in full %Z EST Time zone abbreviation .if t .in -.5i .if n .in -2 .fi If a character other than one of those shown above appears after a percent sign in the format, --- 84,99 ---- %U 10 Sunday-based week number (two digits) %w 3 Day number (one digit, Sunday is 0) %W 10 Monday-based week number (two digits) ! %x 03/08/89 Date* ! %X 14:54:40 Time* %y 89 Last two digits of year %Y 1989 Year in full %Z EST Time zone abbreviation + %+ Wed Mar 8 14:54:40 EST 1989 Default output format* .if t .in -.5i .if n .in -2 + * The exact output depends on the locale. + .sp .fi If a character other than one of those shown above appears after a percent sign in the format, *************** *** 150,153 **** --- 155,175 ---- On BSD-based systems, the adjustment is made by changing the rate at which time advances; on System-V-based systems, the adjustment is made by changing the time. + .SH FILES + .ta \w'/usr/local/etc/zoneinfo/posixrules\0\0'u + /usr/lib/locale/\f2L\fP/LC_TIME description of time locale \f2L\fP + .br + /usr/local/etc/zoneinfo time zone information directory + .br + /usr/local/etc/zoneinfo/localtime local time zone file + .br + /usr/local/etc/zoneinfo/posixrules used with POSIX-style TZ's + .br + /usr/local/etc/zoneinfo/GMT for UTC leap seconds + .sp + If + .B /usr/local/etc/zoneinfo/GMT + is absent, + UTC leap seconds are loaded from + .BR /usr/local/etc/zoneinfo/posixrules . .\" @(#)date.1 7.2 =================================================================== RCS file: RCS/date.c,v retrieving revision 1994.6.1.1 retrieving revision 1994.6.1.2 diff -c -r1994.6.1.1 -r1994.6.1.2 *** date.c 1994/05/05 16:24:49 1994.6.1.1 --- date.c 1994/05/09 09:47:28 1994.6.1.2 *************** *** 40,45 **** --- 40,49 ---- #endif #include "utmp.h" /* for OLD_TIME (or its absence) */ + #if HAVE_SETLOCALE + # include "locale.h" + #endif + /* ** The two things date knows about time are. . . */ *************** *** 485,495 **** (void) time(&now); tm = *localtime(&now); ! if (format == NULL) { ! timeout(stdout, "%a %b ", &tm); ! (void) printf("%2d ", tm.tm_mday); ! timeout(stdout, "%X %Z %Y", &tm); ! } else timeout(stdout, format, &tm); (void) putchar('\n'); (void) fflush(stdout); (void) fflush(stderr); --- 489,498 ---- (void) time(&now); tm = *localtime(&now); ! #if HAVE_SETLOCALE ! setlocale(LC_TIME, ""); ! #endif ! timeout(stdout, format ? format : "%+", &tm); (void) putchar('\n'); (void) fflush(stdout); (void) fflush(stderr); =================================================================== RCS file: RCS/private.h,v retrieving revision 1994.5.1.1 retrieving revision 1994.5.1.2 diff -c -r1994.5.1.1 -r1994.5.1.2 *** private.h 1994/04/03 02:54:41 1994.5.1.1 --- private.h 1994/05/09 09:47:28 1994.5.1.2 *************** *** 30,35 **** --- 30,38 ---- #ifndef HAVE_MKDIR #define HAVE_MKDIR 1 #endif + #ifndef HAVE_SETLOCALE + #define HAVE_SETLOCALE 1 + #endif #ifndef HAVE_SETTIMEOFDAY #define HAVE_SETTIMEOFDAY 3 #endif *************** *** 48,53 **** --- 51,60 ---- #endif #ifndef NEED_TIME_DECL #define NEED_TIME_DECL 0 + #endif + + #ifndef LOCALE_HOME + #define LOCALE_HOME "/usr/lib/locale" #endif /* =================================================================== RCS file: RCS/strftime.c,v retrieving revision 1994.6 retrieving revision 1994.6.1.1 diff -c -r1994.6 -r1994.6.1.1 *** strftime.c 1994/05/05 15:47:58 1994.6 --- strftime.c 1994/05/09 09:48:02 1994.6.1.1 *************** *** 3,10 **** static char elsieid[] = "@(#)strftime.c 7.19"; /* ** Based on the UCB version with the ID appearing below. ! ** This is ANSIish only when time is treated identically in all locales and ! ** when "multibyte character == plain character". */ #endif /* !defined NOID */ #endif /* !defined lint */ --- 3,9 ---- static char elsieid[] = "@(#)strftime.c 7.19"; /* ** Based on the UCB version with the ID appearing below. ! ** This is ANSIish only when "multibyte character == plain character". */ #endif /* !defined NOID */ #endif /* !defined lint */ *************** *** 35,60 **** #endif /* !defined LIBC_SCCS */ #include "tzfile.h" ! static const char afmt[][4] = { ! "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" }; ! static const char Afmt[][10] = { ! "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", ! "Saturday" ! }; ! static const char bfmt[][4] = { ! "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", ! "Oct", "Nov", "Dec" ! }; ! static const char Bfmt[][10] = { ! "January", "February", "March", "April", "May", "June", "July", ! "August", "September", "October", "November", "December" }; static char *_add P((const char *, char *, const char *)); static char *_conv P((int, const char *, char *, const char *)); ! static char *_fmt P((const char *, const struct tm *, char *, const char *)); size_t strftime P((char *, size_t, const char *, const struct tm *)); --- 34,98 ---- #endif /* !defined LIBC_SCCS */ #include "tzfile.h" + #include "fcntl.h" ! struct lc_time { ! const char *mon[12]; ! const char *month[12]; ! const char *wday[7]; ! const char *weekday[7]; ! const char *X_fmt; ! const char *x_fmt; ! const char *c_fmt; ! const char *am; ! const char *pm; ! const char *date_fmt; }; ! ! static const struct lc_time C_time_locale = { ! { ! "Jan", "Feb", "Mar", "Apr", "May", "Jun", ! "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" ! }, { ! "January", "February", "March", "April", "May", "June", ! "July", "August", "September", "October", "November", "December" ! }, { ! "Sun", "Mon", "Tue", "Wed", ! "Thu", "Fri", "Sat" ! }, { ! "Sunday", "Monday", "Tuesday", "Wednesday", ! "Thursday", "Friday", "Saturday" ! }, ! ! /* X_fmt */ ! "%H:%M:%S", ! ! /* ! ** x_fmt ! ** Since the C language standard calls for ! ** "date, using locale's date format," anything goes. ! ** Using just numbers (as here) makes Quakers happier; ! ** it's also compatible with SVR4. ! */ ! "%m/%d/%y", ! ! /* c_fmt */ ! "%a %b %d %H:%M:%S %Y", ! ! "AM", "PM", ! ! /* date_fmt */ ! "%a %b %e %H:%M:%S %Z %Y" }; + #if HAVE_SETLOCALE + # include <locale.h> + #endif + static char *_add P((const char *, char *, const char *)); static char *_conv P((int, const char *, char *, const char *)); ! static char *_fmt P((const char *, const struct tm *, char *, const char *, struct lc_time *)); ! static const struct lc_time *_loc P((struct lc_time *)); size_t strftime P((char *, size_t, const char *, const struct tm *)); *************** *** 68,75 **** const struct tm *t; { char *p; ! p = _fmt(format, t, s, s + maxsize); if (p == s + maxsize) return 0; *p = '\0'; --- 106,117 ---- const struct tm *t; { char *p; + struct lc_time localebuf; ! if (!format) ! format = "%c"; ! localebuf.mon[0] = 0; ! p = _fmt(format, t, s, s + maxsize, &localebuf); if (p == s + maxsize) return 0; *p = '\0'; *************** *** 77,87 **** } static char * ! _fmt(format, t, pt, ptlim) const char *format; const struct tm *t; char *pt; const char *ptlim; { for (; *format; ++format) { if (*format == '%') { --- 119,130 ---- } static char * ! _fmt(format, t, pt, ptlim, locale) const char *format; const struct tm *t; char *pt; const char *ptlim; + struct lc_time *locale; { for (; *format; ++format) { if (*format == '%') { *************** *** 90,114 **** case '\0': --format; break; case 'A': pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? ! "?" : Afmt[t->tm_wday], pt, ptlim); continue; case 'a': pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? ! "?" : afmt[t->tm_wday], pt, ptlim); continue; case 'B': pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? ! "?" : Bfmt[t->tm_mon], pt, ptlim); continue; case 'b': case 'h': pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? ! "?" : bfmt[t->tm_mon], pt, ptlim); continue; case 'c': ! pt = _fmt("%D %X", t, pt, ptlim); continue; case 'C': /* --- 133,166 ---- case '\0': --format; break; + case '+': + pt = _fmt(_loc(locale)->date_fmt, t, + pt, ptlim, locale); + continue; case 'A': pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? ! "?" : _loc(locale)->weekday[t->tm_wday], ! pt, ptlim); continue; case 'a': pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? ! "?" : _loc(locale)->wday[t->tm_wday], ! pt, ptlim); continue; case 'B': pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? ! "?" : _loc(locale)->month[t->tm_mon], ! pt, ptlim); continue; case 'b': case 'h': pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? ! "?" : _loc(locale)->mon[t->tm_mon], ! pt, ptlim); continue; case 'c': ! pt = _fmt(_loc(locale)->c_fmt, t, ! pt, ptlim, locale); continue; case 'C': /* *************** *** 122,148 **** "%02d", pt, ptlim); continue; case 'D': ! pt = _fmt("%m/%d/%y", t, pt, ptlim); ! continue; ! case 'x': ! /* ! ** Version 3.0 of strftime from Arnold Robbins ! ** (arnold(a)skeeve.atl.ga.us) does the ! ** equivalent of... ! ** _fmt("%a %b %e %Y"); ! ** ...for %x; since the X3J11 C language ! ** standard calls for "date, using locale's ! ** date format," anything goes. Using just ! ** numbers (as here) makes Quakers happier. ! ** Word from Paul Eggert (eggert(a)twinsun.com) ! ** is that %Y-%m-%d is the ISO standard date ! ** format, specified in ISO 2014 and later ! ** ISO 8601:1988, with a summary available in ! ** pub/doc/ISO/english/ISO8601.ps.Z on ! ** ftp.uni-erlangen.de. ! ** (ado, 5/30/93) ! */ ! pt = _fmt("%m/%d/%y", t, pt, ptlim); continue; case 'd': pt = _conv(t->tm_mday, "%02d", pt, ptlim); --- 174,180 ---- "%02d", pt, ptlim); continue; case 'D': ! pt = _fmt("%m/%d/%y", t, pt, ptlim, locale); continue; case 'd': pt = _conv(t->tm_mday, "%02d", pt, ptlim); *************** *** 224,240 **** pt, ptlim); continue; case 'R': ! pt = _fmt("%H:%M", t, pt, ptlim); continue; case 'r': ! pt = _fmt("%I:%M:%S %p", t, pt, ptlim); continue; case 'S': pt = _conv(t->tm_sec, "%02d", pt, ptlim); continue; case 'T': ! case 'X': ! pt = _fmt("%H:%M:%S", t, pt, ptlim); continue; case 't': pt = _add("\t", pt, ptlim); --- 256,271 ---- pt, ptlim); continue; case 'R': ! pt = _fmt("%H:%M", t, pt, ptlim, locale); continue; case 'r': ! pt = _fmt("%I:%M:%S %p", t, pt, ptlim, locale); continue; case 'S': pt = _conv(t->tm_sec, "%02d", pt, ptlim); continue; case 'T': ! pt = _fmt("%H:%M:%S", t, pt, ptlim, locale); continue; case 't': pt = _add("\t", pt, ptlim); *************** *** 321,327 **** ** "date as dd-bbb-YYYY" ** (ado, 5/24/93) */ ! pt = _fmt("%e-%b-%Y", t, pt, ptlim); continue; case 'W': pt = _conv((t->tm_yday + 7 - --- 352,358 ---- ** "date as dd-bbb-YYYY" ** (ado, 5/24/93) */ ! pt = _fmt("%e-%b-%Y", t, pt, ptlim, locale); continue; case 'W': pt = _conv((t->tm_yday + 7 - *************** *** 332,337 **** --- 363,376 ---- case 'w': pt = _conv(t->tm_wday, "%d", pt, ptlim); continue; + case 'X': + pt = _fmt(_loc(locale)->X_fmt, t, + pt, ptlim, locale); + continue; + case 'x': + pt = _fmt(_loc(locale)->x_fmt, t, + pt, ptlim, locale); + continue; case 'y': pt = _conv((t->tm_year + TM_YEAR_BASE) % 100, "%02d", pt, ptlim); *************** *** 390,393 **** --- 429,526 ---- while (pt < ptlim && (*pt = *str++) != '\0') ++pt; return pt; + } + + static const struct lc_time * + _loc(locale) + struct lc_time *locale; + { + static const char locale_home[] = LOCALE_HOME; + static const char lc_time[] = "LC_TIME"; + static char *locale_buf; + static char locale_buf_C[] = "C"; + + int fd; + char *lbuf, *name, *p; + const char **ap, *plim; + char filename[FILENAME_MAX]; + struct stat st; + size_t namesize, bufsize; + + /* Use locale->mon[0] to signal whether locale is already set up. */ + if (locale->mon[0]) + return locale; + + #if HAVE_SETLOCALE + name = setlocale(LC_TIME, (char *)0); + #else + if (!(name = getenv("LC_ALL")) || !*name) + if (!(name = getenv(lc_time)) || !*name) + name = getenv("LANG"); + #endif + if (!name || !*name) + goto no_locale; + + /* If the locale name is the same as our cache, use the cache. */ + lbuf = locale_buf; + if (lbuf && strcmp(name, lbuf) == 0) { + p = lbuf; + for (ap=(const char **)locale; ap<(const char **)(locale + 1); ap++) + *ap = p += strlen(p) + 1; + return locale; + } + + /* Slurp the locale file into the cache. */ + namesize = strlen(name) + 1; + if (sizeof(filename) < sizeof(locale_home) + namesize + sizeof(lc_time)) + goto no_locale; + sprintf(filename, "%s/%s/%s", locale_home, name, lc_time); + fd = open(filename, O_RDONLY, 0); + if (fd < 0) + goto no_locale; + if (fstat(fd, &st) != 0) + goto bad_locale; + if (st.st_size <= 0) + goto bad_locale; + bufsize = namesize + st.st_size; + locale_buf = 0; + lbuf = + !lbuf || lbuf==locale_buf_C + ? malloc(bufsize) + : realloc(lbuf, bufsize); + if (!lbuf) + goto bad_locale; + strcpy(lbuf, name); + p = lbuf + namesize; + plim = p + st.st_size; + if (read(fd, p, (size_t)st.st_size) != st.st_size) + goto bad_lbuf; + if (close(fd) != 0) + goto bad_lbuf; + + /* Parse the locale file into *locale. */ + if (plim[-1] != '\n') + goto bad_lbuf; + for (ap=(const char **)locale; ap<(const char **)(locale + 1); ap++) { + if (p == plim) + goto bad_lbuf; + *ap = p; + while (*p != '\n') + p++; + *p++ = 0; + } + + /* Record the successful parse in the cache. */ + locale_buf = lbuf; + + return locale; + + bad_lbuf: + free(lbuf); + bad_locale: + (void) close(fd); + no_locale: + *locale = C_time_locale; + locale_buf = locale_buf_C; + return locale; }

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timezones compatible with POSIX? [forwarded with permisison]
by ado May 8, 1994

May 8, 1994

> From peggyd(a)sco.COM Fri May 6 14:03:24 1994 > Return-Path: <peggyd(a)sco.COM> > Received: from relay1.UU.NET by elsie.nci.nih.gov (4.1/SMI-4.1) > id AA01798; Fri, 6 May 94 14:03:23 EDT > Received: from sco.sco.COM by relay1.UU.NET with SMTP > (5.61/UUNET-internet-primary) id AAwotc03064; Fri, 6 May 94 14:03:19 -0400 > Received: from tehama.sco.COM by sco.sco.COM > id aa08718; Wed, 6 May 70 11:08:32 PDT > Received: from ping.sco.COM by tehama.sco.com id aa00201; 6 May 94 11:00 PDT > From: mommy <peggyd(a)sco.COM> > X-Mailer: SCO System V Mail (version 3.2) > To: ado(a)elsie.nci.nih.gov > Subject: timezones compatible with POSIX? > Cc: peggyd(a)sco.COM > Date: Fri, 6 May 94 10:59:55 PDT > Message-Id: <9405061059.aa21366(a)ping.sco.com> > Status: RO > > > Hello, > > I work at the Santa Cruz Operation, a company that makes > UNIX. I am designing and implementing the part of our > installation that sets time zones. A search for complete, > thorough timezone information led me to your anonymous ftp > site, and I would like to use the information that you make > available, if possible. > > However I am having some trouble reconciling the Rule > format with the format we use, which is also the POSIX standard > for timezone strings (as far as I can tell, looking at my > POSIX doc). The problem is in the area of shifting to and from > Daylight Savings Time. Our format is to use a Julian day, > a month/week/day, or a week/day format. It's different enough from > your Rule format that timezones defined in your format (such as Sun >= 11) > do not work in our format for more than a few years at best (is > that the 2nd week of the month? The 3rd week? It shifts.) > > I am wondering if anyone else has had this problem, and if you > have seen any solutions? Are there alternate ways of expressing > timezones? If you'd like more information I'd be happy to supply > it. > > Thanks very much for your help, > > --peggyd(a)sco.com

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