This is a snippet for retreiving and storing infromation from bluetoothctl

bt-stats-sketch.sh

#!/bin/bash

# this script shows Bluetooth devices information using bluetoothctl and saves it to dir ${B_DIR}

B_DIR=.btop.tmp

shopt -s expand_aliases
alias bl="bluetoothctl"

printf "addr             rssi | first               last                 name \n" ;

mkdir -p ${B_DIR} && bl devices > ${B_DIR}/devicesNow && cat ${B_DIR}/devicesNow | \
while read device; do
  addr=$(echo $device | grep Device | awk '{print $2}') ;
  DEVICE_FILE=${B_DIR}/device-$addr ;
  NEW_DEVICE_FILE="${DEVICE_FILE}.new"

  nowStr=$(date +%Y-%m-%d.%H:%M:%S) ;
  if [ -f ${DEVICE_FILE} ] ; then
    hasFirst=$(cat ${DEVICE_FILE} | grep First) ;
    if [ -z "${hasFirst}" ] ; then
      #echo "Last: $nowStr" > ${DEVICE_FILE} ;
      echo "First: $nowStr" > ${NEW_DEVICE_FILE} ;
    else
      firstVal=$(cat ${DEVICE_FILE} | grep First)
      echo "${firstVal}" > ${NEW_DEVICE_FILE} ;
      echo "Last: $nowStr" >> ${NEW_DEVICE_FILE} ;
    fi

    RSSIList=$(cat ${DEVICE_FILE} | grep 'RSSIList' | sed -r 's/RSSIList: //g') ;

    RSSIListArr=()
    if [ ! -z "${RSSIList}" ] ; then
      RSSIListArr=(${RSSIList// / })
      if [ ${#RSSIListArr[@]} -gt 4 ]; then
        unset 'RSSIListArr[${#RSSIListArr[@]}-1]'
      fi
      if [[ "${RSSIListArr[0]}" -gt "${RSSIListArr[1]}" ]]; then
        RSSIVector='^'
      else
        RSSIVector='v'
      fi
    else
      RSSIVector=' '
    fi
  else
    echo "First: $nowStr" > ${NEW_DEVICE_FILE} ;
    RSSIVector='~'
  fi

  bl info $addr >> ${NEW_DEVICE_FILE} ;

  RSSIList="${rssi} ${RSSIListArr[@]}"
  echo "RSSIList: ${RSSIList}" >> ${NEW_DEVICE_FILE} ;

  name=$(cat ${NEW_DEVICE_FILE} | grep 'Name' | awk '{print $2}') ;
  rssi=$(cat ${NEW_DEVICE_FILE} | grep 'RSSI:' | awk '{print $2}') ;
  first=$(cat ${NEW_DEVICE_FILE} | grep 'First:' | awk '{print $2}') ;
  last=$(cat ${NEW_DEVICE_FILE} | grep 'Last:' | awk '{print $2}') ;
  rssiList=$(cat ${NEW_DEVICE_FILE} | grep 'RSSIList:' | awk '{ s = ""; for (i = 2; i <= NF; i++) s = s $i " "; print s }') ;

  [[ -z ${rssi} ]] && rssi="   "
  [[ -z ${last} ]] && last="                    "

  printf "${addr} ${rssi} ${RSSIVector} ${first} ${last} ${name} " ;
  #printf "${rssiList}"
  printf "\n"
  cp -r ${NEW_DEVICE_FILE} ${DEVICE_FILE}
done