date2ctime

#!/bin/sh
# date2ctime - convert a date string into a Unix time integer
# Steve Kinzler, kinzler@cs.indiana.edu, Jan 00
# http://www.cs.indiana.edu/~kinzler/home.html#unix
# Tweaked cosmetically by Reuben Thomas   10th February 2016

usage="usage: `basename $0` [DATE]"
if [ "$1" = "-h" ]; then
    echo $usage
    exit 0
fi
if [ $# -eq 0 ]; then
    date=`date`
else
    date=$1
fi

echo `date +%s -d "$date"`