epochtime #1

#!/bin/bash
# Contribution from Kent Lewin.
set -u

declare Platform=

# Convert Epoch Time to human-readable format.
if [[ -z "${1:-}" ]]; then
   echo -e "\\nUsage: ${0##*/} <EpocTime>\\n\\nwhere <EpochTime> is a timestamp in Epoch Time form, e.g. 1735646399.\\n"
   exit 1
else
   Platform=$(uname -s)
   if [[ "$Platform" == "Darwin" ]]; then
      date -r "$1" +"%Y-%m-%d-%H%M%S"
   else
      date -d "@$1" +"%Y-%m-%d-%H%M%S"
   fi
fi