[tz] POSIX extension check
eggert at cs.ucla.edu
Mon Sep 9 06:14:51 UTC 2013
Arthur David Olson wrote:
> It's probably worthwhile to check whether extended POSIX in zic-produced
> binaries will cause grief when those binaries are used with old versions of
> localtime.c. If so, one or more of documentation, a zic warning, or a
> version number bump may be in order.
Those suggestions sound good, and I'll soon propose
a patch along those lines.
I checked with the test script appended to the message,
and it looks like we're pretty safe. The only problem
I observed was with America/Godthab for dates past the
start of 2038; this is because the new POSIX TZ string
uses negative hours, which the old tz code does
not grok. I doubt whether the Godthab issue is urgent,
since we are talking only far-future dates here, and
our predictions for them are quite possibly wrong anyway.
omit_junk='s/^[^[:blank:]]*[[:blank:]]*//; s/ UTC / UT /'
for zone in America/Los_Angeles Antarctica/Palmer Asia/Tehran Asia/Gaza Asia/Hebron Pacific/Fiji America/Godthab America/Argentina/San_Luis America/Santiago Pacific/Easter; do
echo $zone report
$o/etc/zdump -v $o/etc/zoneinfo-posix/$zone | sed "$omit_junk" >oo
$o/etc/zdump -v $n/etc/zoneinfo-posix/$zone | sed "$omit_junk" >on
$n/etc/zdump -v $o/etc/zoneinfo-posix/$zone | sed "$omit_junk" >no
$n/etc/zdump -v $n/etc/zoneinfo-posix/$zone | sed "$omit_junk" >nn
set oo on no nn
for i in oo on no; do
case $i in
oo) js='on no nn';;
on) js='no nn';;
for j in $js; do
diff -u $i $j
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