timein() {
zonedir="/usr/share/zoneinfo"
if [ ! -d $zonedir ] ; then
echo "No time zone database at $zonedir." >&2
exit 1
fi
if [ -d "$zonedir/posix" ] ; then
zonedir=$zonedir/posix # Modern Linux systems
fi
if [ $# -eq 0 ] ; then
timezone="UTC"
mixedzone="UTC"
elif [ "$1" = "list" ] ; then
( echo "All known time zones and regions defined on this system:"
cd $zonedir
find -L * -type f -print | xargs -n 2 | \
awk '{ printf " %-38s %-38s\n", $1, $2 }'
) | less
else
region="$(dirname $1)"
zone="$(basename $1)"
# Is the given time zone a direct match? If so, we're good to go.
# Otherwise we need to dig around a bit to find things. Start by
# just counting matches.
matchcnt="$(find -L $zonedir -name $zone -type f -print |\
wc -l | sed 's/[^[:digit:]]//g' )"
# Check if at least one file matches.
if [ "$matchcnt" -gt 0 ] ; then
# But exit if more than one file matches.
if [ $matchcnt -gt 1 ] ; then
echo "\"$zone\" matches more than one possible time zone record." >&2
echo "Please use 'list' to see all known regions and time zones." >&2
Improving on User Commands 75
fi
match="$(find -L $zonedir -name $zone -type f -print)"
mixedzone="$zone"
else # Maybe we can find a matching time zone region, rather than a specific
# time zone.
# First letter capitalized, rest of word lowercase for region + zone
mixedregion="$(echo ${region%${region#?}} \
| tr '[[:lower:]]' '[[:upper:]]')\
$(echo ${region#?} | tr '[[:upper:]]' '[[:lower:]]')"
mixedzone="$(echo ${zone%${zone#?}} | tr '[[:lower:]]' '[[:upper:]]') \
$(echo ${zone#?} | tr '[[:upper:]]' '[[:lower:]]')"
if [ "$mixedregion" != "." ] ; then
# Only look for specified zone in specified region
# to let users specify unique matches when there's
# more than one possibility (e.g., "Atlantic").
match="$(find -L $zonedir/$mixedregion -type f -name $mixedzone -print)"
else
match="$(find -L $zonedir -name $mixedzone -type f -print)"
fi
# If file exactly matched the specified pattern
if [ -z "$match" ] ; then
# Check if the pattern was too ambiguous.
if [ ! -z $(find -L $zonedir -name $mixedzone -type d -print) ] ; then
echo "The region \"$1\" has more than one time zone. " >&2
else # Or if it just didn't produce any matches at all
echo "Can't find an exact match for \"$1\". " >&2
fi
echo "Please use 'list' to see all known regions and time zones." >&2
fi
fi
timezone="$match"
fi
nicetz=$(echo $timezone | sed "s|$zonedir/||g") # Pretty up the output.
echo It\'s $(TZ=$timezone date '+%A, %B %e, %Y, at %l:%M %p') in $nicetz
}