Obtain list of active network services on MacOS

macos-network-servicelist.sh

# improvement of answer https://apple.stackexchange.com/a/223446/183406
# fixes issue where multiple services may have the same hardware port (e.g. USB Ethernet)
get_interfaces() {
  while read -r line; do
      sname="$(echo "$line" | sed -E 's|(.*) \(Hardware Port: (.+), Device: (.+)\)|\1|')"
      hname="$(echo "$line" | sed -E 's|(.*) \(Hardware Port: (.+), Device: (.+)\)|\2|')"
      sdev="$(echo "$line" | sed -E 's|(.*) \(Hardware Port: (.+), Device: (.+)\)|\3|')"
      #echo "Current service: $sname, $sdev, $currentservice"
      if [ -n "$sdev" ]; then
          ifout="$(ifconfig "$sdev" 2>/dev/null)"
          echo "$ifout" | grep 'status: active' > /dev/null 2>&1
          rc="$?"
          if [ "$rc" -eq 0 ]; then
              currentservice="$sname"
              currentdevice="$sdev"
              currentmac=$(echo "$ifout" | awk '/ether/{print $2}')

              # may have multiple active devices, so echo it here
              echo "$currentservice, $currentdevice, $currentmac"
          fi
      fi
  done <<< "$(networksetup -listnetworkserviceorder | awk 'BEGIN { RS = "\\([0-9]\+\\) " ; FS = "\n" } { print $1, $2 }')"

  if [ -z "$currentservice" ]; then
      >&2 echo "Could not find current service"
      exit 1
  fi
}