+ # Determine function return code
+ if [ "$returnState" = "true" ]; then
+ return 0;
+ fi
+} # Exports TZ environment variable
+timeUntilNextDay(){
+ # Desc: Report seconds until next day.
+ # Output: stdout: integer seconds until next day
+ # Output: exit code 0 if stdout > 0; 1 if stdout = 0; 2 if stdout < 0
+ # Usage: timeUntilNextDay
+ # Usage: if ! myTTL="$(timeUntilNextDay)"; then yell "ERROR in if statement"; exit 1; fi
+ local returnState TIME_CURRENT TIME_NEXT_DAY SECONDS_UNTIL_NEXT_DAY
+ TIME_CURRENT="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
+ TIME_NEXT_DAY="$(date -d "$TIME_CURRENT next day" --iso-8601=date)"; # Produce timestamp of beginning of tomorrow with resolution of 1 second.
+ SECONDS_UNTIL_NEXT_DAY="$(( $(date +%s -d "$TIME_NEXT_DAY") - $(date +%s -d "$TIME_CURRENT") ))" ; # Calculate seconds until closest future midnight (res. 1 second).
+ if [[ "$SECONDS_UNTIL_NEXT_DAY" -gt 0 ]]; then
+ returnState="true";
+ elif [[ "$SECONDS_UNTIL_NEXT_DAY" -eq 0 ]]; then
+ returnState="WARNING_ZERO";
+ yell "WARNING:Reported time until next day exactly zero.";
+ elif [[ "$SECONDS_UNTIL_NEXT_DAY" -lt 0 ]]; then
+ returnState="WARNING_NEGATIVE";
+ yell "WARNING:Reported time until next day is negative.";
+ fi
+
+ try echo "$SECONDS_UNTIL_NEXT_DAY"; # Report
+
+ #===Determine function return code===
+ if [[ "$returnState" = "true" ]]; then
+ return 0;
+ elif [[ "$returnState" = "WARNING_ZERO" ]]; then
+ return 1;
+ elif [[ "$returnState" = "WARNING_NEGATIVE" ]]; then
+ return 2;
+ fi
+} # Report seconds until next day
+timeUntilNextHour(){
+ # Desc: Report seconds until next hour
+ # Output: stdout: integer seconds until next hour
+ # Output: exit code 0 if stdout > 0; 1 if stdout = 0; 2 if stdout < 0
+ # Usage: timeUntilNextHour
+ # Usage: if ! myTTL="$(timeUntilNextHour)"; then yell "ERROR in if statement"; exit 1; fi
+ local returnState TIME_CURRENT TIME_NEXT_HOUR SECONDS_UNTIL_NEXT_HOUR
+ TIME_CURRENT="$(date --iso-8601=seconds)"; # Produce `date`-parsable current timestamp with resolution of 1 second.
+ TIME_NEXT_HOUR="$(date -d "$TIME_CURRENT next hour" --iso-8601=hours)"; # Produce `date`-parsable current time stamp with resolution of 1 second.
+ SECONDS_UNTIL_NEXT_HOUR="$(( $(date +%s -d "$TIME_NEXT_HOUR") - $(date +%s -d "$TIME_CURRENT") ))"; # Calculate seconds until next hour (res. 1 second).
+ if [[ "$SECONDS_UNTIL_NEXT_HOUR" -gt 0 ]]; then
+ returnState="true";
+ elif [[ "$SECONDS_UNTIL_NEXT_HOUR" -eq 0 ]]; then
+ returnState="WARNING_ZERO";
+ yell "WARNING:Reported time until next hour exactly zero.";
+ elif [[ "$SECONDS_UNTIL_NEXT_HOUR" -lt 0 ]]; then
+ returnState="WARNING_NEGATIVE";
+ yell "WARNING:Reported time until next hour is negative.";
+ fi
+
+ try echo "$SECONDS_UNTIL_NEXT_HOUR"; # Report
+
+ #===Determine function return code===
+ if [[ "$returnState" = "true" ]]; then
+ return 0;
+ elif [[ "$returnState" = "WARNING_ZERO" ]]; then
+ return 1;
+ elif [[ "$returnState" = "WARNING_NEGATIVE" ]]; then
+ return 2;
+ fi
+} # Report seconds until next hour
+dateTimeShort(){
+ # Desc: Timestamp without separators (YYYYmmddTHHMMSS+zzzz)
+ # Usage: dateTimeShort
+ # Output: stdout: timestamp (ISO-8601, no separators)
+ local TIME_CURRENT TIME_CURRENT_SHORT
+ TIME_CURRENT="$(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.
+ echo "$TIME_CURRENT_SHORT";
+} # Get YYYYmmddTHHMMSS±zzzz
+dateShort(){
+ # Desc: Date without separators (YYYYmmdd)
+ # Usage: dateShort
+ # Output: stdout: date (ISO-8601, no separators)
+ local TIME_CURRENT DATE_CURRENT_SHORT
+ TIME_CURRENT="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
+ DATE_CURRENT_SHORT="$(date -d "$TIME_CURRENT" +%Y%m%d)"; # Produce separator-less current date with resolution 1 day.
+ echo "$DATE_CURRENT_SHORT";
+} # Get YYYYmmdd
+timeDuration(){
+ # Desc: Output approximate time duration string before given time (default:current date)
+ # Ref/Attrib: ISO-8601:2004(E), §4.4.4.2 Representations of time intervals by duration and context information
+ # Note: "1 month" ("P1M") is assumed to be "30 days" (see ISO-8601:2004(E), §2.2.1.2)
+ # Usage: timeDuration [arg1] ([arg2])
+ # Input: arg1: seconds as base 10 integer >= 0 (ex: 3601)
+ # arg2: precision level (optional; default=2)
+ # Output: stdout: ISO-8601 duration string (ex: "P1H1S", "P2Y10M15DT10H30M20S")
+ # Example: 'timeDuration 111111 3' yields 'P1DT6H51M'
+ # Depends: date 8 (gnucoreutils)
+ local returnState fullHours fullMinutes fullSeconds;
+ ARG1="$1";
+ ARG2="$2";
+ precision=2; # set default precision
+ returnState="true"; # set default return state