Check in the pristine copy of ICU 4.6...

icu46/source/tools/tzcode/tzselect.ksh

+#! /bin/ksh
+
+# '@(#)tzselect.ksh     8.1'
+
+# Ask the user about the time zone, and output the resulting TZ value to stdout.
+# Interact with the user via stderr and stdin.
+
+# Contributed by Paul Eggert.
+
+# Porting notes:
+#
+# This script requires several features of the Korn shell.
+# If your host lacks the Korn shell,
+# you can use either of the following free programs instead:
+#
+#       <a href=ftp://ftp.gnu.org/pub/gnu/>
+#       Bourne-Again shell (bash)
+#       </a>
+#
+#       <a href=ftp://ftp.cs.mun.ca/pub/pdksh/pdksh.tar.gz>
+#       Public domain ksh
+#       </a>
+#
+# This script also uses several features of modern awk programs.
+# If your host lacks awk, or has an old awk that does not conform to Posix.2,
+# you can use either of the following free programs instead:
+#
+#       <a href=ftp://ftp.gnu.org/pub/gnu/>
+#       GNU awk (gawk)
+#       </a>
+#
+#       <a href=ftp://ftp.whidbey.net/pub/brennan/>
+#       mawk
+#       </a>
+
+
+# Specify default values for environment variables if they are unset.
+: ${AWK=awk}
+: ${TZDIR=$(pwd)}
+
+# Check for awk Posix compliance.
+($AWK -v x=y 'BEGIN { exit 123 }') </dev/null >/dev/null 2>&1
+[ $? = 123 ] || {
+        echo >&2 "$0: Sorry, your \`$AWK' program is not Posix compatible."
+        exit 1
+}
+
+# Make sure the tables are readable.
+TZ_COUNTRY_TABLE=$TZDIR/iso3166.tab
+TZ_ZONE_TABLE=$TZDIR/zone.tab
+for f in $TZ_COUNTRY_TABLE $TZ_ZONE_TABLE
+do
+        <$f || {
+                echo >&2 "$0: time zone files are not set up correctly"
+                exit 1
+        }
+done
+
+newline='
+'
+IFS=$newline
+
+
+# Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
+case $(echo 1 | (select x in x; do break; done) 2>/dev/null) in
+?*) PS3=
+esac
+
+
+# Begin the main loop.  We come back here if the user wants to retry.
+while
+
+        echo >&2 'Please identify a location' \
+                'so that time zone rules can be set correctly.'
+
+        continent=
+        country=
+        region=
+
+
+        # Ask the user for continent or ocean.
+
+        echo >&2 'Please select a continent or ocean.'
+
+        select continent in \
+            Africa \
+            Americas \
+            Antarctica \
+            'Arctic Ocean' \
+            Asia \
+            'Atlantic Ocean' \
+            Australia \
+            Europe \
+            'Indian Ocean' \
+            'Pacific Ocean' \
+            'none - I want to specify the time zone using the Posix TZ format.'
+        do
+            case $continent in
+            '')
+                echo >&2 'Please enter a number in range.';;
+            ?*)
+                case $continent in
+                Americas) continent=America;;
+                *' '*) continent=$(expr "$continent" : '\([^ ]*\)')
+                esac
+                break
+            esac
+        done
+        case $continent in
+        '')
+                exit 1;;
+        none)
+                # Ask the user for a Posix TZ string.  Check that it conforms.
+                while
+                        echo >&2 'Please enter the desired value' \
+                                'of the TZ environment variable.'
+                        echo >&2 'For example, GST-10 is a zone named GST' \
+                                'that is 10 hours ahead (east) of UTC.'
+                        read TZ
+                        $AWK -v TZ="$TZ" 'BEGIN {
+                                tzname = "[^-+,0-9][^-+,0-9][^-+,0-9]+"
+                                time = "[0-2]?[0-9](:[0-5][0-9](:[0-5][0-9])?)?"
+                                offset = "[-+]?" time
+                                date = "(J?[0-9]+|M[0-9]+\.[0-9]+\.[0-9]+)"
+                                datetime = "," date "(/" time ")?"
+                                tzpattern = "^(:.*|" tzname offset "(" tzname \
+                                  "(" offset ")?(" datetime datetime ")?)?)$"
+                                if (TZ ~ tzpattern) exit 1
+                                exit 0
+                        }'
+                do
+                        echo >&2 "\`$TZ' is not a conforming" \
+                                'Posix time zone string.'
+                done
+                TZ_for_date=$TZ;;
+        *)
+                # Get list of names of countries in the continent or ocean.
+                countries=$($AWK -F'\t' \
+                        -v continent="$continent" \
+                        -v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
+                '
+                        /^#/ { next }
+                        $3 ~ ("^" continent "/") {
+                                if (!cc_seen[$1]++) cc_list[++ccs] = $1
+                        }
+                        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)
+
+
+                # If there's more than one country, ask the user which one.
+                case $countries in
+                *"$newline"*)
+                        echo >&2 'Please select a country.'
+                        select country in $countries
+                        do
+                            case $country in
+                            '') echo >&2 'Please enter a number in range.';;
+                            ?*) break
+                            esac
+                        done
+
+                        case $country in
+                        '') exit 1
+                        esac;;
+                *)
+                        country=$countries
+                esac
+
+
+                # Get list of names of time zone rule regions in the country.
+                regions=$($AWK -F'\t' \
+                        -v country="$country" \
+                        -v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
+                '
+                        BEGIN {
+                                cc = country
+                                while (getline <TZ_COUNTRY_TABLE) {
+                                        if ($0 !~ /^#/  &&  country == $2) {
+                                                cc = $1
+                                                break
+                                        }
+                                }
+                        }
+                        $1 == cc { print $4 }
+                ' <$TZ_ZONE_TABLE)
+
+
+                # If there's more than one region, ask the user which one.
+                case $regions in
+                *"$newline"*)
+                        echo >&2 'Please select one of the following' \
+                                'time zone regions.'
+                        select region in $regions
+                        do
+                                case $region in
+                                '') echo >&2 'Please enter a number in range.';;
+                                ?*) break
+                                esac
+                        done
+                        case $region in
+                        '') exit 1
+                        esac;;
+                *)
+                        region=$regions
+                esac
+
+                # Determine TZ from country and region.
+                TZ=$($AWK -F'\t' \
+                        -v country="$country" \
+                        -v region="$region" \
+                        -v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
+                '
+                        BEGIN {
+                                cc = country
+                                while (getline <TZ_COUNTRY_TABLE) {
+                                        if ($0 !~ /^#/  &&  country == $2) {
+                                                cc = $1
+                                                break
+                                        }
+                                }
+                        }
+                        $1 == cc && $4 == region { print $3 }
+                ' <$TZ_ZONE_TABLE)
+
+                # Make sure the corresponding zoneinfo file exists.
+                TZ_for_date=$TZDIR/$TZ
+                <$TZ_for_date || {
+                        echo >&2 "$0: time zone files are not set up correctly"
+                        exit 1
+                }
+        esac
+
+
+        # Use the proposed TZ to output the current date relative to UTC.
+        # Loop until they agree in seconds.
+        # Give up after 8 unsuccessful tries.
+
+        extra_info=
+        for i in 1 2 3 4 5 6 7 8
+        do
+                TZdate=$(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="
+Local time is now:      $TZdate.
+Universal Time is now:  $UTdate."
+                        break
+                esac
+        done
+
+
+        # Output TZ info and ask the user to confirm.
+
+        echo >&2 ""
+        echo >&2 "The following information has been given:"
+        echo >&2 ""
+        case $country+$region in
+        ?*+?*)  echo >&2 "      $country$newline        $region";;
+        ?*+)    echo >&2 "      $country";;
+        +)      echo >&2 "      TZ='$TZ'"
+        esac
+        echo >&2 ""
+        echo >&2 "Therefore TZ='$TZ' will be used.$extra_info"
+        echo >&2 "Is the above information OK?"
+
+        ok=
+        select ok in Yes No
+        do
+            case $ok in
+            '') echo >&2 'Please enter 1 for Yes, or 2 for No.';;
+            ?*) break
+            esac
+        done
+        case $ok in
+        '') exit 1;;
+        Yes) break
+        esac
+do :
+done
+
+case $SHELL in
+*csh) file=.login line="setenv TZ '$TZ'";;
+*) file=.profile line="TZ='$TZ'; export TZ"
+esac
+
+echo >&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 $0 command in shell scripts:"
+
+echo "$TZ"