aarch64-linux-gnu-5.1/aarch64-linux-gnu/libc/usr/bin/tzselect - toolchains/linux-x86/gcc - Git at Google

 #!/bin/bash

 PKGVERSION="(GNU libc) "
 TZVERSION="2.21"
 REPORT_BUGS_TO="<http://www.gnu.org/software/libc/bugs.html>"

 # 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 a Posix-like shell and prefers the extension of a
 # 'select' statement.  The 'select' statement was introduced in the
 # Korn shell and is available in Bash and other shell implementations.
 # If your host lacks both Bash and the Korn shell, you can get their
 # source from one of these locations:
 #
 #	Bash <http://www.gnu.org/software/bash/bash.html>
 #	Korn Shell <http://www.kornshell.com/>
 #	Public Domain Korn Shell <http://www.cs.mun.ca/~michael/pdksh/>
 #
 # For portability to Solaris 9 /bin/sh this script avoids some POSIX
 # features and common extensions, such as $(...) (which works sometimes
 # but not others), $((...)), and $10.
 #
 # 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,
 # you can use either of the following free programs instead:
 #
 #	Gawk (GNU awk) <http://www.gnu.org/software/gawk/>
 #	mawk <http://invisible-island.net/mawk/>


 # Specify default values for environment variables if they are unset.
 : ${AWK=awk}
 : ${TZDIR=/usr/share/zoneinfo}

 # 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
 }

 coord=
 location_limit=10

 usage="Usage: tzselect [--version] [--help] [-c COORD] [-n LIMIT]
 Select a time zone 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."

 # Ask the user to select from the function's arguments,
 # and assign the selected argument to the variable 'select_result'.
 # Exit on EOF or I/O error.  Use the shell's 'select' builtin if available,
 # falling back on a less-nice but portable substitute otherwise.
 if
   case $BASH_VERSION in
   ?*) : ;;
   '')
     # '; exit' should be redundant, but Dash doesn't properly fail without it.
     (eval 'set --; select x; do break; done; exit') 2>/dev/null
   esac
 then
   # Do this inside 'eval', as otherwise the shell might exit when parsing it
   # even though it is never executed.
   eval '
     doselect() {
       select select_result
       do
 	case $select_result in
 	"") echo >&2 "Please enter a number in range." ;;
 	?*) break
 	esac
       done || exit
     }

     # Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
     case $BASH_VERSION in
     [01].*)
       case `echo 1 | (select x in x; do break; done) 2>/dev/null` in
       ?*) PS3=
       esac
     esac
   '
 else
   doselect() {
     # Field width of the prompt numbers.
     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

       # Prompt and read input.
       printf >&2 %s "${PS3-#? }"
       read select_i || exit
     done
   }
 fi

 while getopts c:n:-: opt
 do
     case $opt$OPTARG in
     c*)
 	coord=$OPTARG ;;
     n*)
 	location_limit=$OPTARG ;;
     -help)
 	exec echo "$usage" ;;
     -version)
 	exec echo "tzselect $PKGVERSION$TZVERSION" ;;
     -*)
 	echo >&2 "$0: -$opt$OPTARG: unknown option; try '$0 --help'"; exit 1 ;;
     *)
 	echo >&2 "$0: try '$0 --help'"; exit 1 ;;
     esac
 done

 shift `expr $OPTIND - 1`
 case $# in
 0) ;;
 *) echo >&2 "$0: $1: unknown argument"; exit 1 ;;
 esac

 # 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


 # Awk script to read a time zone table and output the same table,
 # with each column preceded by its distance from 'here'.
 output_distances='
   BEGIN {
     FS = "\t"
     while (getline <TZ_COUNTRY_TABLE)
       if ($0 ~ /^[^#]/)
         country[$1] = $2
     country["US"] = "US" # Otherwise the strings get too long.
   }
   function convert_coord(coord, deg, min, ilen, sign, sec) {
     if (coord ~ /^[-+]?[0-9]?[0-9][0-9][0-9][0-9][0-9][0-9]([^0-9]|$)/) {
       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)
       min = degmin - intdeg * 100
       deg = (intdeg * 60 + min) / 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 dist(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)
   }
   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 "\t" country[$1]
     if (NF == 4)
       line = line " - " $4
     printf "%g\t%s\n", dist(coord_lat, coord_long, here_lat, here_long), line
   }
 '

 # 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=

 	case $coord in
 	?*)
 		continent=coord;;
 	'')

 	# Ask the user for continent or ocean.

 	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 '"$quoted_continents"' \
 		"coord - I want to use geographical coordinates." \
 		"TZ - I want to specify the time zone using the Posix TZ format."
 	    continent=$select_result
 	    case $continent in
 	    Americas) continent=America;;
 	    *" "*) continent=`expr "$continent" : '\''\([^ ]*\)'\''`
 	    esac
 	'
 	esac

 	case $continent in
 	TZ)
 		# 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;;
 	*)
 		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 "${location_limit}q"
 		    `
 		    regions=`echo "$distance_table" | $AWK '
 		      BEGIN { FS = "\t" }
 		      { print $NF }
 		    '`
 		    echo >&2 'Please select one of the following' \
 			    'time zone regions,'
 		    echo >&2 'listed roughly in increasing order' \
 			    "of distance from $coord".
 		    doselect $regions
 		    region=$select_result
 		    TZ=`echo "$distance_table" | $AWK -v region="$region" '
 		      BEGIN { FS="\t" }
 		      $NF == region { print $4 }
 		    '`
 		    ;;
 		*)
 		# Get list of names of countries in the continent or ocean.
 		countries=`$AWK \
 			-v continent="$continent" \
 			-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
 		'
 			BEGIN { FS = "\t" }
 			/^#/ { 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' \
 				'whose clocks agree with yours.'
 			doselect $countries
 			country=$select_result;;
 		*)
 			country=$countries
 		esac


 		# Get list of names of time zone rule regions in the country.
 		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
 					}
 				}
 			}
 			$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.'
 			doselect $regions
 			region=$select_result;;
 		*)
 			region=$regions
 		esac

 		# Determine TZ from country and region.
 		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
 					}
 				}
 			}
 			$1 == cc && $4 == region { print $3 }
 		' <$TZ_ZONE_TABLE`
 		esac

 		# 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%$coord in
 	?*%?*%)	echo >&2 "	$country$newline	$region";;
 	?*%%)	echo >&2 "	$country";;
 	%?*%?*) echo >&2 "	coord $coord$newline	$region";;
 	%%?*)	echo >&2 "	coord $coord";;
 	+)	echo >&2 "	TZ='$TZ'"
 	esac
 	echo >&2 ""
 	echo >&2 "Therefore TZ='$TZ' will be used.$extra_info"
 	echo >&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

 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"
	#!/bin/bash

	PKGVERSION="(GNU libc) "
	TZVERSION="2.21"
	REPORT_BUGS_TO="<http://www.gnu.org/software/libc/bugs.html>"

	# 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 a Posix-like shell and prefers the extension of a
	# 'select' statement. The 'select' statement was introduced in the
	# Korn shell and is available in Bash and other shell implementations.
	# If your host lacks both Bash and the Korn shell, you can get their
	# source from one of these locations:
	#
	# Bash <http://www.gnu.org/software/bash/bash.html>
	# Korn Shell <http://www.kornshell.com/>
	# Public Domain Korn Shell <http://www.cs.mun.ca/~michael/pdksh/>
	#
	# For portability to Solaris 9 /bin/sh this script avoids some POSIX
	# features and common extensions, such as $(...) (which works sometimes
	# but not others), $((...)), and $10.
	#
	# 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,
	# you can use either of the following free programs instead:
	#
	# Gawk (GNU awk) <http://www.gnu.org/software/gawk/>
	# mawk <http://invisible-island.net/mawk/>


	# Specify default values for environment variables if they are unset.
	: ${AWK=awk}
	: ${TZDIR=/usr/share/zoneinfo}

	# 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
	}

	coord=
	location_limit=10

	usage="Usage: tzselect [--version] [--help] [-c COORD] [-n LIMIT]
	Select a time zone 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."

	# Ask the user to select from the function's arguments,
	# and assign the selected argument to the variable 'select_result'.
	# Exit on EOF or I/O error. Use the shell's 'select' builtin if available,
	# falling back on a less-nice but portable substitute otherwise.
	if
	case $BASH_VERSION in
	?*) : ;;
	'')
	# '; exit' should be redundant, but Dash doesn't properly fail without it.
	(eval 'set --; select x; do break; done; exit') 2>/dev/null
	esac
	then
	# Do this inside 'eval', as otherwise the shell might exit when parsing it
	# even though it is never executed.
	eval '
	doselect() {
	select select_result
	do
	case $select_result in
	"") echo >&2 "Please enter a number in range." ;;
	?*) break
	esac
	done \|\| exit
	}

	# Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
	case $BASH_VERSION in
	[01].*)
	case `echo 1 \| (select x in x; do break; done) 2>/dev/null` in
	?*) PS3=
	esac
	esac
	'
	else
	doselect() {
	# Field width of the prompt numbers.
	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

	# Prompt and read input.
	printf >&2 %s "${PS3-#? }"
	read select_i \|\| exit
	done
	}
	fi

	while getopts c:n:-: opt
	do
	case $opt$OPTARG in
	c*)
	coord=$OPTARG ;;
	n*)
	location_limit=$OPTARG ;;
	-help)
	exec echo "$usage" ;;
	-version)
	exec echo "tzselect $PKGVERSION$TZVERSION" ;;
	-*)
	echo >&2 "$0: -$opt$OPTARG: unknown option; try '$0 --help'"; exit 1 ;;
	*)
	echo >&2 "$0: try '$0 --help'"; exit 1 ;;
	esac
	done

	shift `expr $OPTIND - 1`
	case $# in
	0) ;;
	*) echo >&2 "$0: $1: unknown argument"; exit 1 ;;
	esac

	# 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


	# Awk script to read a time zone table and output the same table,
	# with each column preceded by its distance from 'here'.
	output_distances='
	BEGIN {
	FS = "\t"
	while (getline <TZ_COUNTRY_TABLE)
	if ($0 ~ /^[^#]/)
	country[$1] = $2
	country["US"] = "US" # Otherwise the strings get too long.
	}
	function convert_coord(coord, deg, min, ilen, sign, sec) {
	if (coord ~ /^[-+]?[0-9]?[0-9][0-9][0-9][0-9][0-9][0-9]([^0-9]\|$)/) {
	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)
	min = degmin - intdeg * 100
	deg = (intdeg * 60 + min) / 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 dist(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)
	}
	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 "\t" country[$1]
	if (NF == 4)
	line = line " - " $4
	printf "%g\t%s\n", dist(coord_lat, coord_long, here_lat, here_long), line
	}
	'

	# 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=

	case $coord in
	?*)
	continent=coord;;
	'')

	# Ask the user for continent or ocean.

	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 '"$quoted_continents"' \
	"coord - I want to use geographical coordinates." \
	"TZ - I want to specify the time zone using the Posix TZ format."
	continent=$select_result
	case $continent in
	Americas) continent=America;;
	" ") continent=`expr "$continent" : '\''\([^ ]*\)'\''`
	esac
	'
	esac

	case $continent in
	TZ)
	# 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;;
	*)
	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 "${location_limit}q"
	`
	regions=`echo "$distance_table" \| $AWK '
	BEGIN { FS = "\t" }
	{ print $NF }
	'`
	echo >&2 'Please select one of the following' \
	'time zone regions,'
	echo >&2 'listed roughly in increasing order' \
	"of distance from $coord".
	doselect $regions
	region=$select_result
	TZ=`echo "$distance_table" \| $AWK -v region="$region" '
	BEGIN { FS="\t" }
	$NF == region { print $4 }
	'`
	;;
	*)
	# Get list of names of countries in the continent or ocean.
	countries=`$AWK \
	-v continent="$continent" \
	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
	'
	BEGIN { FS = "\t" }
	/^#/ { 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' \
	'whose clocks agree with yours.'
	doselect $countries
	country=$select_result;;
	*)
	country=$countries
	esac


	# Get list of names of time zone rule regions in the country.
	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
	}
	}
	}
	$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.'
	doselect $regions
	region=$select_result;;
	*)
	region=$regions
	esac

	# Determine TZ from country and region.
	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
	}
	}
	}
	$1 == cc && $4 == region { print $3 }
	' <$TZ_ZONE_TABLE`
	esac

	# 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%$coord in
	?%?%) echo >&2 " $country$newline $region";;
	?*%%) echo >&2 " $country";;
	%?%?) echo >&2 " coord $coord$newline $region";;
	%%?*) echo >&2 " coord $coord";;
	+) echo >&2 " TZ='$TZ'"
	esac
	echo >&2 ""
	echo >&2 "Therefore TZ='$TZ' will be used.$extra_info"
	echo >&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

	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"