3 # Desc: Template to display date and time.
5 yell
() { echo "$0: $*" >&2; } #o Yell, Die, Try Three-Fingered Claw technique
6 die
() { yell
"$*"; exit 111; } #o Ref/Attrib: https://stackoverflow.com/a/25515370
7 try
() { "$@" || die
"cannot $*"; } #o
9 # Desc: Timestamp without separators (YYYYmmddTHHMMSS+zzzz)
10 # Usage: dateTimeShort ([str date])
12 # Input: arg1: 'date'-parsable timestamp string (optional)
13 # Output: stdout: timestamp (ISO-8601, no separators)
15 local argTime timeCurrent timeInput timeCurrentShort
19 timeCurrent
="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
20 # Decide to parse current or supplied date
21 ## Check if time argument empty
22 if [[ -z "$argTime" ]]; then
23 ## T: Time argument empty, use current time
24 timeInput
="$timeCurrent";
26 ## F: Time argument exists, validate time
27 if date --date="$argTime" 1>/dev
/null
2>&1; then
28 ### T: Time argument is valid; use it
31 ### F: Time argument not valid; exit
32 yell
"ERROR:Invalid time argument supplied. Exiting."; exit 1;
35 # Construct and deliver separator-les date string
36 timeCurrentShort
="$(date -d "$timeInput" +%Y%m%dT%H%M%S%z)";
37 echo "$timeCurrentShort";
38 } # Get YYYYmmddTHHMMSS±zzzz
40 #==BEGIN sample code==
41 echo "The current day and time is :$(dateTimeShort)";
42 echo "Contact lost with STS-107 on:$(dateTimeShort "2003-02-01T08:59:15-05:00")";
43 echo "Bitcoin started on :$(dateTimeShort "@
1231006505")";
44 testDate
="2020-07-07T02:30:11,690097074+00:00";
45 echo "This string was generated using 'date --iso-8601=ns':$testDate";
46 echo "Using dateTimeShort, it appears as:$(dateTimeShort "$testDate")";
49 # Author: Steven Baltakatei Sandoval