To GitHub and everyone: please use UTC timestamps when there are potential readers outside of your timezone. Since every technical person should know their current UTC difference, calculating the local time is easy.
Awww, that's so optimistic.
"At some point in their career, every programmer must pass through the fires of timezone hell."
(Esoteric software-engineering topics could make a wonderful video game, you know?)
It took a bit longer than I expected.
Along with the recommendation to never inventing your own cryptography, you should also never write your own date/time routines. Use well tested functions in your database or programming language libraries.
Anyway come feb 29th 2008 I get a call about some users were having issues. After not to long I figured out it was caused because of the leap year and his logic did not account for leap years. So I called them back and told them it would fix its self by tomorrow. I never actually bothered to fix the bug because a) I thought it was unlikely that the pos system would still be used in 4 years and b) the code was so bad in all areas that trying to fix anything had a good chance of breaking something else.
Lets just say that job was very character building
Much of the code assumed that all times were in PST and the commenter had apparently been incorporating data sources from other time zones into the code. I thought it was pretty funny.
> Greenwich Mean Time (GMT) originally referred to the mean solar time at the Royal Observatory in Greenwich, London, which later became adopted as a global time standard. It is for the most part the same as Coordinated Universal Time (UTC), and when this is viewed as a time zone, the name Greenwich Mean Time is especially used by bodies connected with the United Kingdom, such as the BBC World Service, the Royal Navy, the Met Office and others particularly in Arab countries, such as the Middle East Broadcasting Center and OSN. It is the term in common use in the United Kingdom and countries of the Commonwealth, including Australia, South Africa, India, Pakistan and Malaysia, and many other countries in the Eastern Hemisphere.
> Before the introduction of UTC on 1 January 1972, Greenwich Mean Time (also known as Zulu time) was the same as Universal Time (UT), a standard astronomical concept used in many technical fields.
> In the United Kingdom, GMT is the official time during winter; during summer British Summer Time (BST) is used. GMT is the same as Western European Time.
Google does this conversion automatically on their own outage pages.
show New York time 14:25 in your local time zone: ~$ date --date 'TZ="America/New_York" 2014-03-14 14:25'
show New York time 14:25 in Alberta time zone: ~$ TZ="Australia/Alberta" date --date 'TZ="America/New_York" 2014-03-14 14:25'
On a GNU/Linux system, for more timezone strings see ls -Ral /usr/share/zoneinfo/
You can get the local time with JS, and you can get UTC, and from those two you can narrow it down (you know the current UTC offset, but that's it), but you're not going to get a single answer.
Now that I think about it, you could auto-suggest based on offset and embed a list of locations per option if they needed to pick between daylight savings or not, for instance. There's room for an interesting widget or service, but it would need to be updated almost as much as a US sales tax calculation widget ;-)
I've always seen it refered to as AEST/AEDT, reducing the ambiguity.
[1] http://en.wikipedia.org/wiki/List_of_time_zone_abbreviations