Check if TCP port 25 is open

(echo >/dev/tcp/localhost/25) &>/dev/null && echo "TCP port 25 open" || echo "TCP port 25 close"
Check trough unix sockets if tcp port is open or close
Sample Output
TCP port 25 close

By: YouM
2013-11-12 02:11:01

5 Alternatives + Submit Alt

What Others Think

lsof -i | grep "25\|smtp"
adria · 444 weeks and 3 days ago
If you can't write the program yourself, try reading about this essay first. Maybe you have a school assignment with these processes, or maybe you need to write an essay on success? Then just visit, I did this every time I couldn't write my own essay.
EthanVaughan · 57 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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