Convert integers to Extended Value format (bourne shell):
ev_map="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-." int_to_ev() { int="${1}" if [ ! "${int}" ] then printf "__" return fi [ "${int}" -lt 0 ] && int=0 [ "${int}" -gt 4095 ] && int=4095 hob=$(( ( ${int} / 64 ) + 1 )) lob=$(( ( ${int} % 64 ) + 1 )) printf "%s%s" "$(echo "${ev_map}" | cut -c${hob})" "$(echo "${ev_map}" | cut -c${lob})" }