On Feb 20, 2025, at 12:37 PM, Brooks Harris via tz <tz@iana.org> wrote:
> On 2025-02-20 02:45 PM, Paul Eggert via tz wrote: > >> In other words, users don't really want true System V compatibility. They >> just want to keep using the same name for US eastern time. > > That's true for most users. But not necessarily for special cases. > > For example, some professional video facilities might find it better to > ignore DST shifts to avoid discontinuities in the SMPTE video timecode, which > cannot tolerate a DST shift in some cases, essentially choosing to run > "permanent stand time". Yes, the display time would not match the local wall > clock in summer time, but that is less important than continuous > uninterrupted time. EST5EDT and the others (PST8PDT and such) give > administrators that option. What option? EST5EDT isn't permanent stand(and) time, it supports DST, following some unspecified-by-the-setting rules. If you want *permanent standard time* for the UTC-5:00 time zone, that'd be "EST5", which does *not* correspond to a tzdb file; it works as a TZ setting because the tz code parses TZ POSIX/SV-style if it doesn't correspond to a file.
