diff options
Diffstat (limited to 'timezone/etcetera')
| -rw-r--r-- | timezone/etcetera | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/timezone/etcetera b/timezone/etcetera index 4fb27acff3..f87a76ea48 100644 --- a/timezone/etcetera +++ b/timezone/etcetera @@ -1,4 +1,4 @@ -# @(#)etcetera 7.10 +# @(#)etcetera 7.11 # These entries are mostly present for historical reasons, so that # people in areas not otherwise covered by the tz files could "zic -l" @@ -24,10 +24,24 @@ Link Etc/GMT Etc/GMT-0 Link Etc/GMT Etc/GMT+0 Link Etc/GMT Etc/GMT0 -# We use POSIX-style signedness in the names and output, -# internal-style signedness in the specifications. -# For example, TZ=Etc/GMT+4 corresponds to 4 hours _behind_ UTC; -# it is equivalent to TZ=GMT+4, which is implemented directly as per POSIX. +# We use POSIX-style signs in the Zone names and the output abbreviations, +# even though this is the opposite of what many people expect. +# POSIX has positive signs west of Greenwich, but many people expect +# positive signs east of Greenwich. For example, TZ='Etc/GMT+4' uses +# the abbreviation "GMT+4" and corresponds to 4 hours behind UTC +# (i.e. west of Greenwich) even though many people would expect it to +# mean 4 hours ahead of UTC (i.e. east of Greenwich). +# +# In the draft 5 of POSIX 1003.1-200x, the angle bracket notation +# (which is not yet supported by the tz code) allows for +# TZ='<GMT-4>+4'; if you want time zone abbreviations conforming to +# ISO 8601 you can use TZ='<-0400>+4'. Thus the commonly-expected +# offset is kept within the angle bracket (and is used for display) +# while the POSIX sign is kept outside the angle bracket (and is used +# for calculation). +# +# Do not use a TZ setting like TZ='GMT+4', which is four hours behind +# GMT but uses the completely misleading abbreviation "GMT". # Earlier incarnations of this package were not POSIX-compliant, # and had lines such as |