date
Table of Contents
date reference
date -u
# └─ --utc
# Fri Aug 18 06:57:31 UTC 2017
date -R
# └─ --rfc─2822
# Fri, 18 Aug 2017 15:55:42 +0900
date '+%Y%m%dT%H%M%S'
# 20170818T144038
TZ='America/Los_Angeles' date
# Fri Aug 18 00:01:11 PDT 2017
date -d '2days ago'
# └─ --date, display time described by STRING, not 'now'
# Wed Aug 16 16:05:03 KST 2017
date -d '2days ago' '+%Y%m%dT%H%M%S'
# 20170816T160622
date --iso-8601
# 2017-08-18
date --iso-8601=seconds
# └─ also can be 'auto', 'hours', 'minutes', 'ns'
# 2017-08-18T17:12:30+09:00
date --utc --iso-8601=seconds
# 2017-08-18T08:12:49+00:00