[tz] [PATCH] Change abbreviation of Sri Lanka standard time to SLST

[Paul Eggert]

On 10/19/2016 02:40 AM, Guy Harris wrote:
> it's not clear what constraints, if any, are placed on the members of tzname[] if TZ is set to :{tzid} or just to {tzid}, e.g. :Europe/Berlin or Europe/Berlin.

POSIX itself places few constraints on tzname if the TZ environment 
variable is a tzid. However, version 2 and later of the tzfile format 
mostly defers to POSIX for its newline-enclosed, 
POSIX-TZ-environment-variable-style strings (used for time stamps far in 
the future), and this limits us to the POSIX-blessed characters for time 
zone abbreviations of future time stamps. Although I suppose we could 
change the tzfile format to extend the character set, that's not 
something to be done lightly, as I suppose other software relies on 
things like separating time zone abbreviations with commas, colons, 
spaces, etc.