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some Pacific time zones and offsets as of 2026-08-19; observations on Linux, Unix, MacOS, iOS timezone handling

Crossing the Pacific westwards, the ship's time gets set back one hour at a time.  The ship's management arranges it so that at land stops, it is synchronised with the location.  Changes between one stop and the next are somewhat arbitrary, but the idea should be to keep changes smooth and have dawn and dusk at sensible wall times. I set around 5 clocks at each change. The Casio F-91W is the easiest.  I set the hour back using the three buttons on the watch.  The only annoyance is that I have to cycle +23 hours, as one can not decrement the hour directly.  It's not that annoying, and one knows it's going to work. For the Debian (Linux) laptop, I change the /etc/localtime symlink to point to location in /usr/share/zoneinfo/*/*, such as /usr/share/zoneinfo/America/Vancouver.  This is fine when there is a well-known city to select.  It sometimes involves research and experimentation to choose one with the correct (current) offset.  Once the symlink c...

Apple's Time Zone Catastrophe

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In " apple conflates time zone and time offset in the middle of MacOS ", we learned about conceptual muddle around time zones and offsets in MacOS's settings. Since then, I have set the Time Zone to St John's Newfoundland.  In the process, I learned just how primitive Apple's "MacOS" software is. I unchecked "Set time zone automatically using your current location".  I clicked in "Closest city" and started typing.  I was going for St John's.  After a few letters, there were no matches in the interactive matching.  I hit return anyway, and got the following: As if to validate its claim that an extension process had "exited", the depicted pane remained completely empty after I dismissed the "dialog" "box". I turned off and on again the settings window, and researched the topic.  Apparently you have to type it exactly to match what it's expecting, or it doesn't match and crashes.  In this case. ...

apple conflates time zone and time offset in the middle of MacOS

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Following on from " difference between timezone and offset ", Apple makes this mistake right in the middle of MacOS: No, dipshits, "British Summer Time" is not a time zone.  It is an offset, of plus one.  The time zone is London or what-have-you.  They are COMPLETELY DIFFERENT THINGS.

printing wraparound labels with a pt7600

A bit like  https://wibblement.blogspot.com/2025/03/printing-cable-labels-with-pt7600.html , but printing just one wraparound label per id. Using the labeller's cutter, you would have to engage in the whole printing process, and cut when it says.  Doing it this way, you can quickly cut with scissors, either as a batch, or as you need them.  * prepare labeller: insert 9mm black on white tape, power on, ensure barcode PROTOCOL is set to CODE128  * press Code then Z to enter settings, and select CUT 2 using up and down, and hit return  * clear text with code, backspace, enter  * press "Bar Code" (confirm again it says CODE128)  * enter first id in sequence (you are managing ranges / sequences of ids elsewhere), for example "wibble1234", press return  * press Code -> Label Type  * it says Copies 1.  Press 2  * press right arrow and it goes to NUMBER OFF  * press down for 99, or enter however many you want (we don't expect it to...

changing linux timezone

Easy way to change system timezone is to change where the /etc/localtime symlink points to, eg:     # ln -sf /usr/share/zoneinfo/America/St_Johns /etc/localtime 

difference between timezone and offset

This is something I tried and failed to explain to a Computer Science graduate some years ago.  The Computer Science graduate assumed I was trying to make a point about seconds difference between UTC and GMT.  No.  I hope this doesn't count as slop, but Gemini can put it pretty well: User Question 1 what is the conceptual difference betwen a timezone and an offset AI Response 1 While they both help us tell time across the globe, a time zone and an offset are fundamentally different concepts. An offset is a static mathematical calculation, while a time zone is a dynamic geographic region governed by local laws. What is an Offset? An offset is the exact amount of time added to or subtracted from Coordinated Universal Time (UTC) to get the local time. Format: It is always expressed as a plus or minus sign followed by hours and minutes (e.g., +01:00 or -05:00). Nature: It is purely digital and mathematical. Limitation: It does not account for daylight saving time (DST) o...

Taxi ranks without taxis

Today, Folkestone Central taxi rank does not have any taxis, in the early afternoon. Yesterday, Oxford train station taxi rank did not have any taxis, also early afternoon. Later, I had to explain multiple times to a taxi driver where Richer Sounds is. It’s on Botley Road, with a sign outside saying “Richer Sounds”, and large lettering on the building saying “Richer Sounds”. This is second tine in a row a taxi driver has failed to find it, and has instead placed a series of calls asking where it is.