Check connection to host (e.g. check connection to port 80 and 22 of google.com)

Trick copyright: Bash-Oneliner <https://github.com/onceupon/Bash-Oneliner>

nc -vw5 google.com 80
# Connection to google.com 80 port [tcp/http] succeeded!

nc -vw5 google.com 22
# nc: connect to google.com port 22 (tcp) timed out: Operation now in progress
# nc: connect to google.com port 22 (tcp) failed: Network is unreachable

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