ping heise.de -c 300 -ni 0.5 | awk -F '[= ]' {'print $(NF-1)'} | grep -E '[0-9]' > /tmp/ipv4.dat
ping6 heise.de -c 300 -ni 0.5 | awk -F '[= ]' {'print $(NF-1)'} | grep -E '[0-9]' > /tmp/ipv6.dat

cat << EOF > /tmp/ping-rtt.gpi
#!/usr/bin/gnuplot
set terminal svg size 1000,600 fname "Gill Sans" fsize 14 rounded dashed
set style line 80 lt 0
set style line 80 lt rgb "#808080"
set style line 81 lt 3
set style line 81 lt rgb "#808080" lw 0.5
set grid back linestyle 81
set border 3 back linestyle 80
set xtics nomirror
set ytics nomirror
set style line 1 lt 1
set style line 2 lt 1
set style line 3 lt 1
set style line 4 lt 1
set style line 1 lt rgb "#A00000" lw 2 pt 7
set style line 2 lt rgb "#00A000" lw 2 pt 9
set style line 3 lt rgb "#5060D0" lw 2 pt 5
set style line 4 lt rgb "#F25900" lw 2 pt 13
set output "ping-rtt.svg"
set xlabel "Ping [#]"
set ylabel "RTT [ms]"
set key bottom right
plot "/tmp/ipv4.dat" title "IPv4" ls 1, \
   "/tmp/ipv6.dat"  title "IPv6" ls 2
EOF

gnuplot /tmp/ping-rtt.gpi
inkscape --export-png=/tmp/ping-rtt.png ping-rtt.svg

feh -F /tmp/ping.png