@geerlingguy
$ cat /usr/local/bin/when#!/bin/bashif [ -z "$(echo "$1" | egrep "^[0-9]{10,19}$")" ]; then echo "Usage: $0 epoch" 1>&2 exit 1fi
t=${1:0:10}nano=${1:10}
date -d @$t "+%Y-%m-%d %H:%M:%S"