PKGVERSION='(tzcode) '
TZVERSION=see_Makefile
REPORT_BUGS_TO=tz@iana.org
: ${AWK=awk}
: ${TZDIR=`pwd`}
say() {
printf '%s\n' "$1"
}
($AWK -v x=y 'BEGIN { exit 123 }') </dev/null >/dev/null 2>&1
[ $? = 123 ] || {
say >&2 "$0: Sorry, your '$AWK' program is not Posix compatible."
exit 1
}
coord=
location_limit=10
zonetabtype=zone1970
usage="Usage: tzselect [--version] [--help] [-c COORD] [-n LIMIT]
Select a timezone interactively.
Options:
-c COORD
Instead of asking for continent and then country and then city,
ask for selection from time zones whose largest cities
are closest to the location with geographical coordinates COORD.
COORD should use ISO 6709 notation, for example, '-c +4852+00220'
for Paris (in degrees and minutes, North and East), or
'-c -35-058' for Buenos Aires (in degrees, South and West).
-n LIMIT
Display at most LIMIT locations when -c is used (default $location_limit).
--version
Output version information.
--help
Output this help.
Report bugs to $REPORT_BUGS_TO."
if
case $BASH_VERSION in
?*) : ;;
'')
(eval 'set --; select x; do break; done; exit') </dev/null 2>/dev/null
esac
then
eval '
doselect() {
select select_result
do
case $select_result in
"") echo >&2 "Please enter a number in range." ;;
?*) break
esac
done || exit
}
'
else
doselect() {
select_width=`expr $# : '.*'`
select_i=
while :
do
case $select_i in
'')
select_i=0
for select_word
do
select_i=`expr $select_i + 1`
printf >&2 "%${select_width}d) %s\\n" $select_i "$select_word"
done ;;
*[!0-9]*)
echo >&2 'Please enter a number in range.' ;;
*)
if test 1 -le $select_i && test $select_i -le $#; then
shift `expr $select_i - 1`
select_result=$1
break
fi
echo >&2 'Please enter a number in range.'
esac
printf >&2 %s "${PS3-#? }"
read select_i || exit
done
}
fi
while getopts c:n:t:-: opt
do
case $opt$OPTARG in
c*)
coord=$OPTARG ;;
n*)
location_limit=$OPTARG ;;
t*) zonetabtype=$OPTARG ;;
-help)
exec echo "$usage" ;;
-version)
exec echo "tzselect $PKGVERSION$TZVERSION" ;;
-*)
say >&2 "$0: -$opt$OPTARG: unknown option; try '$0 --help'"; exit 1 ;;
*)
say >&2 "$0: try '$0 --help'"; exit 1 ;;
esac
done
shift `expr $OPTIND - 1`
case $# in
0) ;;
*) say >&2 "$0: $1: unknown argument"; exit 1 ;;
esac
TZ_COUNTRY_TABLE=$TZDIR/iso3166.tab
TZ_ZONE_TABLE=$TZDIR/$zonetabtype.tab
for f in $TZ_COUNTRY_TABLE $TZ_ZONE_TABLE
do
<"$f" || {
say >&2 "$0: time zone files are not set up correctly"
exit 1
}
done
$AWK 'BEGIN { u12345 = "\360\222\215\205"; exit length(u12345) != 1 }' || {
{ tmp=`(mktemp -d) 2>/dev/null` || {
tmp=${TMPDIR-/tmp}/tzselect.$$ &&
(umask 77 && mkdir -- "$tmp")
};} &&
trap 'status=$?; rm -fr -- "$tmp"; exit $status' 0 HUP INT PIPE TERM &&
(iconv -f UTF-8 -t //TRANSLIT <"$TZ_COUNTRY_TABLE" >$tmp/iso3166.tab) \
2>/dev/null &&
TZ_COUNTRY_TABLE=$tmp/iso3166.tab &&
iconv -f UTF-8 -t //TRANSLIT <"$TZ_ZONE_TABLE" >$tmp/$zonetabtype.tab &&
TZ_ZONE_TABLE=$tmp/$zonetabtype.tab
}
newline='
'
IFS=$newline
output_distances='
BEGIN {
FS = "\t"
while (getline <TZ_COUNTRY_TABLE)
if ($0 ~ /^[^#]/)
country[$1] = $2
country["US"] = "US" # Otherwise the strings get too long.
}
function abs(x) {
return x < 0 ? -x : x;
}
function min(x, y) {
return x < y ? x : y;
}
function convert_coord(coord, deg, minute, ilen, sign, sec) {
if (coord ~ /^[-+]?[0-9]?[0-9][0-9][0-9][0-9][0-9][0-9]([^0-9]|$)/) {
degminsec = coord
intdeg = degminsec < 0 ? -int(-degminsec / 10000) : int(degminsec / 10000)
minsec = degminsec - intdeg * 10000
intmin = minsec < 0 ? -int(-minsec / 100) : int(minsec / 100)
sec = minsec - intmin * 100
deg = (intdeg * 3600 + intmin * 60 + sec) / 3600
} else if (coord ~ /^[-+]?[0-9]?[0-9][0-9][0-9][0-9]([^0-9]|$)/) {
degmin = coord
intdeg = degmin < 0 ? -int(-degmin / 100) : int(degmin / 100)
minute = degmin - intdeg * 100
deg = (intdeg * 60 + minute) / 60
} else
deg = coord
return deg * 0.017453292519943296
}
function convert_latitude(coord) {
match(coord, /..*[-+]/)
return convert_coord(substr(coord, 1, RLENGTH - 1))
}
function convert_longitude(coord) {
match(coord, /..*[-+]/)
return convert_coord(substr(coord, RLENGTH))
}
# Great-circle distance between points with given latitude and longitude.
# Inputs and output are in radians. This uses the great-circle special
# case of the Vicenty formula for distances on ellipsoids.
function gcdist(lat1, long1, lat2, long2, dlong, x, y, num, denom) {
dlong = long2 - long1
x = cos(lat2) * sin(dlong)
y = cos(lat1) * sin(lat2) - sin(lat1) * cos(lat2) * cos(dlong)
num = sqrt(x * x + y * y)
denom = sin(lat1) * sin(lat2) + cos(lat1) * cos(lat2) * cos(dlong)
return atan2(num, denom)
}
# Parallel distance between points with given latitude and longitude.
# This is the product of the longitude difference and the cosine
# of the latitude of the point that is further from the equator.
# I.e., it considers longitudes to be further apart if they are
# nearer the equator.
function pardist(lat1, long1, lat2, long2) {
return abs(long1 - long2) * min(cos(lat1), cos(lat2))
}
# The distance function is the sum of the great-circle distance and
# the parallel distance. It could be weighted.
function dist(lat1, long1, lat2, long2) {
return gcdist(lat1, long1, lat2, long2) + pardist(lat1, long1, lat2, long2)
}
BEGIN {
coord_lat = convert_latitude(coord)
coord_long = convert_longitude(coord)
}
/^[^#]/ {
here_lat = convert_latitude($2)
here_long = convert_longitude($2)
line = $1 "\t" $2 "\t" $3
sep = "\t"
ncc = split($1, cc, /,/)
for (i = 1; i <= ncc; i++) {
line = line sep country[cc[i]]
sep = ", "
}
if (NF == 4)
line = line " - " $4
printf "%g\t%s\n", dist(coord_lat, coord_long, here_lat, here_long), line
}
'
while
echo >&2 'Please identify a location' \
'so that time zone rules can be set correctly.'
continent=
country=
region=
case $coord in
?*)
continent=coord;;
'')
echo >&2 'Please select a continent, ocean, "coord", or "TZ".'
quoted_continents=`
$AWK '
BEGIN { FS = "\t" }
/^[^#]/ {
entry = substr($3, 1, index($3, "/") - 1)
if (entry == "America")
entry = entry "s"
if (entry ~ /^(Arctic|Atlantic|Indian|Pacific)$/)
entry = entry " Ocean"
printf "'\''%s'\''\n", entry
}
' <"$TZ_ZONE_TABLE" |
sort -u |
tr '\n' ' '
echo ''
`
eval '
doselect '"$quoted_continents"' \
"coord - I want to use geographical coordinates." \
"TZ - I want to specify the timezone using the Posix TZ format."
continent=$select_result
case $continent in
Americas) continent=America;;
*" "*) continent=`expr "$continent" : '\''\([^ ]*\)'\''`
esac
'
esac
case $continent in
TZ)
while
echo >&2 'Please enter the desired value' \
'of the TZ environment variable.'
echo >&2 'For example, AEST-10 is abbreviated' \
'AEST and is 10 hours'
echo >&2 'ahead (east) of Greenwich,' \
'with no daylight saving time.'
read TZ
$AWK -v TZ="$TZ" 'BEGIN {
tzname = "(<[[:alnum:]+-]{3,}>|[[:alpha:]]{3,})"
time = "(2[0-4]|[0-1]?[0-9])" \
"(:[0-5][0-9](:[0-5][0-9])?)?"
offset = "[-+]?" time
mdate = "M([1-9]|1[0-2])\\.[1-5]\\.[0-6]"
jdate = "((J[1-9]|[0-9]|J?[1-9][0-9]" \
"|J?[1-2][0-9][0-9])|J?3[0-5][0-9]|J?36[0-5])"
datetime = ",(" mdate "|" jdate ")(/" time ")?"
tzpattern = "^(:.*|" tzname offset "(" tzname \
"(" offset ")?(" datetime datetime ")?)?)$"
if (TZ ~ tzpattern) exit 1
exit 0
}'
do
say >&2 "'$TZ' is not a conforming Posix timezone string."
done
TZ_for_date=$TZ;;
*)
case $continent in
coord)
case $coord in
'')
echo >&2 'Please enter coordinates' \
'in ISO 6709 notation.'
echo >&2 'For example, +4042-07403 stands for'
echo >&2 '40 degrees 42 minutes north,' \
'74 degrees 3 minutes west.'
read coord;;
esac
distance_table=`$AWK \
-v coord="$coord" \
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
"$output_distances" <"$TZ_ZONE_TABLE" |
sort -n |
sed "${location_limit}q"
`
regions=`say "$distance_table" | $AWK '
BEGIN { FS = "\t" }
{ print $NF }
'`
echo >&2 'Please select one of the following timezones,' \
echo >&2 'listed roughly in increasing order' \
"of distance from $coord".
doselect $regions
region=$select_result
TZ=`say "$distance_table" | $AWK -v region="$region" '
BEGIN { FS="\t" }
$NF == region { print $4 }
'`
;;
*)
countries=`$AWK \
-v continent="$continent" \
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
'
BEGIN { FS = "\t" }
/^#/ { next }
$3 ~ ("^" continent "/") {
ncc = split($1, cc, /,/)
for (i = 1; i <= ncc; i++)
if (!cc_seen[cc[i]]++) cc_list[++ccs] = cc[i]
}
END {
while (getline <TZ_COUNTRY_TABLE) {
if ($0 !~ /^#/) cc_name[$1] = $2
}
for (i = 1; i <= ccs; i++) {
country = cc_list[i]
if (cc_name[country]) {
country = cc_name[country]
}
print country
}
}
' <"$TZ_ZONE_TABLE" | sort -f`
case $countries in
*"$newline"*)
echo >&2 'Please select a country' \
'whose clocks agree with yours.'
doselect $countries
country=$select_result;;
*)
country=$countries
esac
regions=`$AWK \
-v country="$country" \
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
'
BEGIN {
FS = "\t"
cc = country
while (getline <TZ_COUNTRY_TABLE) {
if ($0 !~ /^#/ && country == $2) {
cc = $1
break
}
}
}
/^#/ { next }
$1 ~ cc { print $4 }
' <"$TZ_ZONE_TABLE"`
case $regions in
*"$newline"*)
echo >&2 'Please select one of the following timezones.'
doselect $regions
region=$select_result;;
*)
region=$regions
esac
TZ=`$AWK \
-v country="$country" \
-v region="$region" \
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
'
BEGIN {
FS = "\t"
cc = country
while (getline <TZ_COUNTRY_TABLE) {
if ($0 !~ /^#/ && country == $2) {
cc = $1
break
}
}
}
/^#/ { next }
$1 ~ cc && $4 == region { print $3 }
' <"$TZ_ZONE_TABLE"`
esac
TZ_for_date=$TZDIR/$TZ
<"$TZ_for_date" || {
say >&2 "$0: time zone files are not set up correctly"
exit 1
}
esac
extra_info=
for i in 1 2 3 4 5 6 7 8
do
TZdate=`LANG=C TZ="$TZ_for_date" date`
UTdate=`LANG=C TZ=UTC0 date`
TZsec=`expr "$TZdate" : '.*:\([0-5][0-9]\)'`
UTsec=`expr "$UTdate" : '.*:\([0-5][0-9]\)'`
case $TZsec in
$UTsec)
extra_info="
Selected time is now: $TZdate.
Universal Time is now: $UTdate."
break
esac
done
echo >&2 ""
echo >&2 "The following information has been given:"
echo >&2 ""
case $country%$region%$coord in
?*%?*%) say >&2 " $country$newline $region";;
?*%%) say >&2 " $country";;
%?*%?*) say >&2 " coord $coord$newline $region";;
%%?*) say >&2 " coord $coord";;
*) say >&2 " TZ='$TZ'"
esac
say >&2 ""
say >&2 "Therefore TZ='$TZ' will be used.$extra_info"
say >&2 "Is the above information OK?"
doselect Yes No
ok=$select_result
case $ok in
Yes) break
esac
do coord=
done
case $SHELL in
*csh) file=.login line="setenv TZ '$TZ'";;
*) file=.profile line="TZ='$TZ'; export TZ"
esac
test -t 1 && say >&2 "
You can make this change permanent for yourself by appending the line
$line
to the file '$file' in your home directory; then log out and log in again.
Here is that TZ value again, this time on standard output so that you
can use the $0 command in shell scripts:"
say "$TZ"