The 2018e release of the tz code and data is available. It reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Briefly: North Korea switches back to +09 on 2018-05-05. The main format uses negative DST again, for Ireland etc. 'make tarballs' now also builds a rearguard tarball. New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines. Changes to past and future time stamps North Korea switches back from +0830 to +09 on 2018-05-05. (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon, and Tim Parenti.) Bring back the negative-DST changes of 2018a, except be more compatible with data parsers that do not support negative DST. Also, this now affects historical time stamps in Namibia and the former Czechoslovakia, not just Ireland. The main format now uses negative DST to model time stamps in Europe/Dublin (from 1971 on), Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This does not affect UT offsets, only time zone abbreviations and the tm_isdst flag. Also, this does not affect rearguard or vanguard formats; effectively the main format now uses vanguard instead of rearguard format. Data parsers that do not support negative DST can still use data from the rearguard tarball described below. Changes to build procedure The command 'make tarballs' now also builds the tarball tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz except that it uses rearguard format intended for trailing-edge data parsers. Changes to data format and to code The SAVE column of Rule and Zone lines can now have an 's' or 'd' suffix, which specifies whether the adjusted time is standard time or daylight saving time. If no suffix is given, daylight saving time is used if and only if the SAVE column is nonzero; this is the longstanding behavior. Although this new feature is not used in tzdata, it could be used to specify the legal time in Namibia 1994-2017, as opposed to the popular time (see below). Changes to past time stamps From 1994 through 2017 Namibia observed DST in winter, not summer. That is, it used negative DST, as Ireland still does. This change does not affect UTC offsets; it affects only the tm_isdst flag and the abbreviation used during summer, which is now CAT, not WAST. Although (as noted by Michael Deckers) summer and winter time were both simply called "standard time" in Namibian law, in common practice winter time was considered to be DST (as noted by Stephen Colebourne). The full effect of this change is only in vanguard format; in rearguard and main format, the tm_isdst flag is still zero in winter and nonzero in summer. In 1946/7 Czechoslovakia also observed negative DST in winter. The full effect of this change is only in vanguard format; in rearguard and main formats, it is modeled as plain GMT without daylight saving. Also, the dates of some 1944/5 DST transitions in Czechoslovakia have been changed. Here are links to the release files: https://www.iana.org/time-zones/repository/releases/tzcode2018e.tar.gz https://www.iana.org/time-zones/repository/releases/tzdata2018e.tar.gz https://www.iana.org/time-zones/repository/releases/tzdb-2018e.tar.lz As usual, links to the latest release files are here: https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz Links are also available via plain HTTP, and via FTP from ftp://ftp.iana.org/tz/releases with the same basenames as above. Each release file has a GPG signature, which can be retrieved by appending ".asc" to the above URLs. Copies of these signatures are appended to this message. This release corresponds to commit 4758e88f99c71af65d73ce730e87438466032a5f dated 2018-05-01 23:42:51 -0700 and tagged '2018e' in the development GitHub repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: 4a245cae2d0922b24539a94cf4a8ccc2bba1ee696e0aaefecb41c7c8d78724a7fcea6039909336177b8b26fec8fc47719e3e56ca9839dbaf52f9a4fec84d4717 tzcode2018e.tar.gz d059fcd381b2f6ecdafcd68fdd2a00451d1bf9b1affeb164ae7cabca2e022d499e77f0706ec3f3091b8e84c2211aa66da6c90937108771f1bf070cfebc105cae tzdata2018e.tar.gz afb7569cc9faef6e3d2be16ceef65f8531ac123dac14e3b40a4f54dab916e930b09eb665458e55f98398c4b8c5d108f34985a42bf711b2170de90d819bf0e630 tzdb-2018e.tar.lz Here are the GPG checksums for the release files: -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9nAAoJEO2X6Q5iqn40r+EQAJSt3ap8G8swYPzBg6TstckZ tOxrDcGlRu4km6jzIhHelOwj2Sxw8X/0JyRc09xbGbXGE/mv35DrzKC8ijfazu9pg Mr4eOclfFGq8l48aRag86hR33k62K84Xdl0WrwVFVefhlsRel9i6lXnBFcmgHl/C vSwJXyrZ2DgvZH88B6j8qnYkw/BMbsTKLM1L/3EHxKZqq/TCHS19Z1XbbkF6mm/u 73aHHmXEnpSVol+3aekEKuS+PSdc+loYaAMvibBJ34ci2bc1X1HkOPF30dRSTETW pVtKXp1qFtmHRR07I28l7/jEzmI+XPheCswhOKowWqKe59tA2CTiFnkhuBQUmoZS XDjKpcgvrad9RSES1aVAfVn2iCx78Inu0W8UIWZ/eiMOh0taQH3n7K1KBnLwCEKd rAB9ummGRK787XJEe2/xnH/h0lilU7Ye6EddNwuGf5Q3PlS9brDov66dnIUWi76L uPRTufummczt6XcA9YL0zEhwvAzjSSqQzoga7mXBKSIwakRoKXCIoux+EdQOWNOy /VUMH5NIkND+kRcRdqTXs93Whu7SCV14DKi5j1LL39YC8nqGi0q3u8wndm22AhCr ZR9uMv1Qq1iCXb09sIBfdi7bf0S8348jz1deb/d7jgJ4ISBR7v8UiR3Z/JO8hiPR QSP93j37rjAsFyBSWMxq =knlj -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9nAAoJEO2X6Q5iqn40qYUQAI21DF4x+Qr9uhMf5UL3u/UI BnLTeDqc4t1oLbuuJsbtgausc/m6EIgo2j9+uadXefnguP4fwKHJ2doReuRZ3njI hGnqP2+yCfTRNrZYBU3p6U+/OJq8r/UBsn9aGxNStcZHe6FswnxXWlzpRNbPdNBC nGeYMs2HOQjcdG08BF1sjGm4FC/NS6bugNhs0EcrMLaVa+c0keRWNg9o7Y/SvrZB awFAMz4LhOog2qxhGWtFgSVRAAj5aEDqugOXZL27VszgGPexiAaMCFyQARIHigIw 959D7RYmpeNuEeP6XbzGFgDO6aMbxahoUpP9cCOUI6qKShtDKnY2XkjPmVQiAfjZ zvpsE1dYbWyVTWqWhWL3z0lPCFN6B4eneY6UXY/KtENRl1jEafKN5/7JqKOMBSRo umE1Jy6qSSz5jLuz5pX59iOXWZETIlwtAW6lKe2s6l9xWPL9R8xXoPvbQRadqDxB uANcGZSrKD1jKuybPJa/6BZRF+FlldCkZVVKSSdXuPLF1HhohlvFZqi1WPmWvGd+ s/1+3OhWzB4BHyrp3Wbtj+ZwCtg9UVbJLBM2bgL9nGEyv/1XSxgLJEp3rneIMpJv AMK8rr3XehXLDkXAfx68Mzs3F4lYEdXk6y9f9ZsVj+IdBotwzzjJWeCfnlmJM52y 8cCrPGUjdneFidV9OZ+J =4LFO -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9pAAoJEO2X6Q5iqn40EBwP/1fxMc1IozcXCWSm+h/XZ3M+ bImmIdf8Ws/FZC5yXHWkU4n3DZN6A2Xf/dDTDaZPeyhL3rjd6ju0zxTsQpxdqRms FrEiqlq2CpIVe+pY4EeowfsFdKVYIxtiTw9BNytaDOIgYxRmokNUQusaHw2qrZg6 t6giUhH6bh1/YgZakFP65WItjESR8Dg4aJ7X1f8BJkSEyy9I2lnyWOG7LwB8xNvS YRPRjkVqdVXzdS9MtqO+U5b9pe1MvU6q0lRAOwUvZsGfB7fULkdQcS1XaYDVRdPA WdMKqn21S+oRHYzX5/BZHE68uGFlufPohikYfSCO6pk8eqDe0xbkOl6fpgjjqTZf wCAcZBBoCP11lH8Omdu8bW6LJ0q1jkwuCZxmLBPwonInoByPO/TeDstYSp39KCv2 +w0pl87uYe6/IEwSC1bH0HBF8kzcEq5q5JVHLyqwOKrAm6Nfm5sC5vWFhk3GmMGU FGpFLnwUJlTefy9X3ds8zEvmCAiFMisu5cciMRwfCLvTHSObRGEXtp5pxpr0VhBf A6Qc+83JPTwhEWdVQMVbEWRkkJNG50xAwOhjJaClXjjlvJqQtpUPHLR7fRaQWvm8 sCXhh+PeWpgIbbzaE7TzkVu9sLUGiIvbLiP2yNMOuoZp+UUnrsSaswbeCl0bkGe3 LSswAxioa5rs8zd8WtZe =/AeX -----END PGP SIGNATURE----- PS. If your tzdata parser does not yet support negative DST offsets,this particular release's data entries are also available in arearguard-format tarball and signature that does not contain suchoffsets. This is intended to be a temporary transition aid for theseparsers. The URLs are: https://web.cs.ucla.edu/~eggert/tz/release/2018e/tzdata2018e-rearguard.tar.g... https://web.cs.ucla.edu/~eggert/tz/release/2018e/tzdata2018e-rearguard.tar.g... with the following SHA-512 and GPG checksums: dd92cf2d01388d52731db7569360e3c7e673c3189c8cba807d031fb6b6ce8c115d3f4de3be1c7a6b1e038fa919efdd254cdd4f7731c3130b447dee2c7c5814a4 tzdata2018e-rearguard.tar.gz -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9oAAoJEO2X6Q5iqn40jJMP+gKGNy3VBhJ9B2/plNXta2nH M5fAwJphPXutCv2ums0LPVNbi0FWjPo9T2/6Lmy71vyyusW/9ltS+/bECSnmrZRO VEql2UWghxGMaV3Y2wpFI2XGqepQYsT9Xa1tgXUvXHakQPYe5Osx0J3P50F9ROMy kiWR4VSsSE3IZDiZC32HQjcHsREcUtpgYfn943Zr1Go2FRnp2esnbN0eQtTV5vJW uSYWdfSNWNsSqXR9O2cq9kzCeVKxZjjs2hi1adIrQLzQKy26RXUC9f4tepzRrPfT euHiHUrZXE5p2161Q702P1Nw3zPFrA/SHiFZTpP84mri60RVZTWPP21ityktFukt B+Ebkpd7EwyyFFZB1grbnb1uLc2qkM76gKtIPJAtkWEe7BwwwREh9d/92K/L9XTe opehULRUjX65UyOWNUD9dl3aiy1FHQyWAuX3fRF1u2vrh3WSuIHbO0Uq9RCMQtHP VSY45Ldwv3+PGfyaKlQvftqFAFJ2kjmIC7zQZe5HmBIYG8TIyUCS/P17XZzIrEpw aBNrPe4hV63DSVEvBYLHaCPMMIASASBvSZ2S5Rb2HopAzVd6xOYSvGCqwjdtFpr6 1bD4EeIb2wBxPWH8KFZiSDYK/FpfhuZR7teY6bzG+fsZMtzChP4pcQrebMD3RIPZ RBDXrhtfn+5b78wn6VMM =VPo7 -----END PGP SIGNATURE-----