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Logic for determining the date/time format

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  • Last reply by palswim

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In my quest to display my messages with the ISO date format (yyyy-mm-dd), I determined that I needed to set a locale that would have the date format I desired, whether an existing locale or creating a custom locale.

I had read that the en_DK locale might provide what I wanted, and a quick call to LC_TIME=en_DK date +'%x' verified that it output the ISO-standard format. However, starting Thunderbird (LC_TIME=en_DK.UTF-8 gtk-launch thunderbird), Thunderbird displayed dates for my messages in a different format. But, when I started Thunderbird with the sv_SE locale (LC_TIME=sv_SE.UTF-8 gtk-launch thunderbird), Thunderbird did display the dates in the ISO format. Where does Thunderbird retrieve its date format, and why does it differ from date +'%x'?

In my quest to display my messages with the ISO date format (<i>yyyy-mm-dd</i>), I determined that I needed to set a locale that would have the date format I desired, whether an existing locale or creating a custom locale. I had read that [https://unix.stackexchange.com/q/62316/13308 the <b>en_DK</b> locale might provide what I wanted], and a quick call to <code>LC_TIME=en_DK date +'%x'</code> verified that it output the ISO-standard format. However, starting Thunderbird (<code>LC_TIME=en_DK.UTF-8 gtk-launch thunderbird</code>), Thunderbird displayed dates for my messages in a different format. But, when I started Thunderbird with the <b>sv_SE</b> locale (<code>LC_TIME=sv_SE.UTF-8 gtk-launch thunderbird</code>), Thunderbird did display the dates in the ISO format. Where does Thunderbird retrieve its date format, and why does it differ from <code>date +'%x'</code>?

Modified by palswim

All Replies (2)

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Try checking the setting in Edit > preferences > advanced > general.

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Matt said

Try checking the setting in Edit > preferences > advanced > general.

You mean the Date and Time Formatting setting, with the options to choose between Application locale and Regional settings locale?

That setting did switch locales upon restart, but using the en_DK locale, Thunderbird still formatted the date differently than LC_TIME=en_DK date +'%x'.