# Desc: Template to display date and time.
+yell() { echo "$0: $*" >&2; } #o Yell, Die, Try Three-Fingered Claw technique
+die() { yell "$*"; exit 111; } #o Ref/Attrib: https://stackoverflow.com/a/25515370
+try() { "$@" || die "cannot $*"; } #o
dateTimeShort(){
# Desc: Timestamp without separators (YYYYmmddTHHMMSS+zzzz)
- # Usage: dateTimeShort
+ # Usage: dateTimeShort ([str date])
+ # Version 1.1.0
+ # Input: arg1: 'date'-parsable timestamp string (optional)
# Output: stdout: timestamp (ISO-8601, no separators)
+ # Depends: yell
local TIME_CURRENT TIME_CURRENT_SHORT
+
+ argTime="$1";
+ # Get Current Time
TIME_CURRENT="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
- TIME_CURRENT_SHORT="$(date -d "$TIME_CURRENT" +%Y%m%dT%H%M%S%z)"; # Produce separator-less current timestamp with resolution 1 second.
+ # Decide to parse current or supplied date
+ ## Check if time argument empty
+ if [[ -z "$argTime" ]]; then
+ ## T: Time argument empty, use current time
+ TIME_INPUT="$TIME_CURRENT";
+ else
+ ## F: Time argument exists, validate time
+ if date --date="$argTime" 1>/dev/null 2>&1; then
+ ### T: Time argument is valid; use it
+ TIME_INPUT="$argTime";
+ else
+ ### F: Time argument not valid; exit
+ yell "ERROR:Invalid time argument supplied. Exiting."; exit 1;
+ fi
+ fi
+ # Construct and deliver separator-les date string
+ TIME_CURRENT_SHORT="$(date -d "$TIME_INPUT" +%Y%m%dT%H%M%S%z)";
echo "$TIME_CURRENT_SHORT";
-} # Get date&time without separators
+} # Get YYYYmmddTHHMMSS±zzzz
#==BEGIN sample code==
-echo "The current day and time is:$(dateTimeShort)"
+echo "The current day and time is :$(dateTimeShort)";
+echo "Contact lost with STS-107 on:$(dateTimeShort "2003-02-01T08:59:15-05:00")";
+echo "Bitcoin started on :$(dateTimeShort "@1231006505")";
+testDate="2020-07-07T02:30:11,690097074+00:00";
+echo "This string was generated using 'date --iso-8601=ns':$testDate";
+echo "Using dateTimeShort, it appears as:$(dateTimeShort "$testDate")";
#==END sample code==
# Author: Steven Baltakatei Sandoval