bash number of seconds to human readable time

sectotime.sh

#!/bin/bash

if [ $# -ne 1 ]; then
    echo "Usage:" >&2
    echo "  $(basename $0) <sec>" >&2
    exit 1
fi

function secToTime() {
    local s=$1
    local hh=$(($s / 60 / 60))
    local mm=$(( ($s - $hh * 60 * 60) / 60 ))
    local ss=$(( $s % 60 ))

    printf "%02d:%02d:%02d" "$hh" "$mm" "$ss"
}

secToTime $1
echo