VIM / date / sed / grep / awk

vim:
Line Number:
:%s/^/\=line(".")/


date --date="next day"
date --date="1 days ago"
date --date="-1 days ago"
date --date='6 months 15 day'
date --date='2 months 5 day ago'
$ date --date='2 year ago' # past
$ date --date='3 years' # go into future
$ date --date='2 days' # future
$ date --date='1 month ago' # past
$ date --date='2 months' # future

date --set='+30 minutes'
date --date='1970-01-01 00:00:01 UTC +5 hours' +%s