Bash Timing Function. Takes <start_time> <title> [<timezone}]

time_elapsed.sh

#!/bin/bash

#Outputs
# <title> Start:  4:30:01pm End:  4:33:05pm Elapsed:  0:03:04

# Script behaves same as function. i.e. you can copy the function out.

time_elapsed(){
    timezone=${3-"America/Denver"} #Defaults to Mountain Time
    resume_time=$(date)
    resume_time_seconds=$(date --date="$resume_time" +%s)
    begin_time_seconds=$(date --date="$1" +%s)
    elapsed_seconds=$(( $resume_time_seconds - $begin_time_seconds ))
    elapsed_time=$(printf "%2g:%02d:%02d\n" $(( elapsed_seconds / 3600 )) $(( elapsed_seconds /60 )) $(( elapsed_seconds % 60)))
    printf "$2 Start: %s End: %s Elapsed: %8.8s\n" "$(TZ="$timezone" date --date="$1" +%_I:%M:%S%P)" "$(TZ="$timezone" date --date="$resume_time" +%_I:%M:%S%P)" $elapsed_time
}

time_elapsed "$1" "$2" "$3"