Lire
cat < /dev/tcp/127.0.0.1/22
Tester la connexion
echo > /dev/tcp/127.0.0.1/22
exec 3<>/dev/tcp/www.google.com/80 echo -e "GET / HTTP/1.1\r\nhost: http://www.google.com\r\nConnection: close\r\n\r\n" >&3 cat <&3 exec 3>&-
timeout 1 bash -c " echo > /dev/tcp/${HOST}/${PORT} " > /dev/null 2>&1 && echo "Port ${PORT} is open" || echo "Port ${PORT} is closed"
Ou encore
curl -v telnet://127.0.0.1:22