-#!/bin/bash
-# Desc: Template to report seconds until beginning of next day
-
-#==BEGIN Define script parameters==
-#===BEGIN Declare local script functions===
-yell() { echo "$0: $*" >&2; } # Yell, Die, Try Three-Fingered Claw technique; # Ref/Attrib: https://stackoverflow.com/a/25515370
-die() { yell "$*"; exit 111; }
-try() { "$@" || die "cannot $*"; }
-timeUntilNextDay(){
- # Desc: Report seconds until next day.
- # Version: 1.0.3
- # Output: stdout: integer seconds until next day
- # Output: exit code 0 if stdout > 0; 1 if stdout = 0; 2 if stdout < 0
- # Usage: timeUntilNextDay
- # Usage: if ! myTTL="$(timeUntilNextDay)"; then yell "ERROR in if statement"; exit 1; fi
- # Depends: date 8, echo 8, yell, try
-
- local returnState timeCurrent timeNextDay secondsUntilNextDay
- timeCurrent="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
- timeNextDay="$(date -d "$timeCurrent next day" --iso-8601=date)"; # Produce timestamp of beginning of tomorrow with resolution of 1 second.
- secondsUntilNextDay="$(( $(date +%s -d "$timeNextDay") - $(date +%s -d "$timeCurrent") ))" ; # Calculate seconds until closest future midnight (res. 1 second).
- if [[ "$secondsUntilNextDay" -gt 0 ]]; then
- returnState="true";
- elif [[ "$secondsUntilNextDay" -eq 0 ]]; then
- returnState="warning_zero";
- yell "WARNING:Reported time until next day exactly zero.";
- elif [[ "$secondsUntilNextDay" -lt 0 ]]; then
- returnState="warning_negative";
- yell "WARNING:Reported time until next day is negative.";
- fi
-
- try echo "$secondsUntilNextDay"; # Report
-
- # Determine function return code
- if [[ "$returnState" = "true" ]]; then
- return 0;
- elif [[ "$returnState" = "warning_zero" ]]; then
- return 1;
- elif [[ "$returnState" = "warning_negative" ]]; then
- return 2;
- fi
-} # Report seconds until next day
-#===END Declare local script functions===
-#==END Define script parameters==
-
-
-#==BEGIN sample code==
-try echo "Time until next day (seconds):$(timeUntilNextDay)" # simple report
-
-if ! myTTL="$(timeUntilNextDay)"; then yell "ERROR in if statement for myTTL:$myTTL"; exit 1; fi # Use of exit code to exit early if time <= 0.
-#==END sample code==
-
-# Author: Steven Baltaktei Sandoval
-# License: GPLv3+