1. build binary and output it into ./bin/pkt:
  make
  make build

2. build binary (1) but with additional logging to ./bin/out:
  make GCC_OPTS="-D DBG"

3. prerequisites for using IP geolocation, AS and PROXY ID
   obtain ip2db csvs from https://lite.ip2location.com:
     IP2LOCATION-LITE-DB11.CSV
     IP2LOCATION-LITE-ASN.CSV
     IP2LOCATION-LITE-PX11.CSV
   create tmpfs for better perf (or not, and rely on page cache)
     mkdir -p bin/tmp && mount -t tmpfs -o size=2G ip2db_tmpfs ./bin/tmp
   place downloaded csvs into bin/tmp dir
   
   
4. running.
     ./pkt -g0 -dppp0 -p -i0
   opts:
     -g 0     = group by all columns. same as: -gszxcv
     -g szxcv = grouping options
                -s = packet summary
                -z = source IP4/6
                -x = dst IP4/6
                -c = source udp/tcp port
                -v = dst udp/tcp port
     -dppp0   = replace it with device on which you want to listen. for example:
                   -deth0 or -dlo or -dtun0 or -dwlan0
     -p       = use ss and try to identify process associated with socket
     -i0      = use IP2LDB (see 3) to obtain ip geo, asn, and proxy info.
                same as -igap ([g]eo [a]sn [p]roxy)