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Commands tagged nc from sorted by
Terminal - Commands tagged nc - 32 results
nmap -p 80 hostname
nc -zw2 www.example.com 80 && echo open
2009-12-07 21:35:25
User: sputnick
Functions: echo
Tags: netcat nc
6

@putnamhill, no need if statement in that case.

&& is a AND and || is a OR

if (nc -zw2 www.example.com 80); then echo open; fi
for i in {21..29}; do nc -v -n -z -w 1 192.168.0.$i 443; done
2009-09-25 03:31:29
User: rez0r
9

Simple one-liner for scanning a range of hosts, you can also scan a range of ports with Netcat by ex.: nc -v -n -z -w 1 192.168.0.1 21-443

Useful when Nmap is not available:)

Range declaration like X..X "for i in {21..29}" is only works with bash 3.0+

echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | head -n5 | tail -1 | cut -f2 -d-
On target: "nc -l 4000 | tar xvf -" On source: "tar -cf - . | nc target_ip 4000"
2009-06-30 19:36:19
User: tiagofischer
Tags: tar nc
9

It bypasses encryption overhead of SSH and depending on configuration can be significantly faster.

It's recommended to use only in trusted networks.

function my_irc { tmp=`mktemp`; cat > $tmp; { echo -e "USER $username x x :$ircname\nNICK $nick\nJOIN $target"; while read line; do echo -e "PRIVMSG $target :$line"; done < $tmp; } | nc $server > /dev/null ; rm $tmp; }
2009-06-11 22:14:48
User: Josay
Functions: cat echo read rm
Tags: netcat irc nc
1
command | my_irc

Pipe whatever you want to this function, it will, if everything goes well, be redirected to a channel or a user on an IRC server.

Please note that :

- I am not responsible of flood excesses you might provoke.

- that function does not reply to PINGs from the server. That's the reason why I first write in a temporary file. Indeed, I don't want to wait for inputs while being connected to the server. However, according to the configuration of the server and the length of your file, you may timeout before finishing.

- Concerning the server, the variable content must be on the form "irc.server.org 6667" (or any other port). If you want to make some tests, you can also create a fake IRC server on "localhost 55555" by using

netcat -l -p 55555

- Concerning the target, you can choose a channel (beginning with a '#' like "#chan") or a user (like "user")

- The other variables have obvious names.