Netcat is a simple but powerful utility program that reads and writes data across network connections, using TCP or UDP protocol, IPv4 or IPv6, with a variety of functions.

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versions of netcat

I've tried the two main versions of netcat : GNU and BSD. (mine is BSD Version). On GNU version, the command $ nc -l -p 12345 works fine but with BSD, option -l (listen) can't be used in conjonction ...
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Differences in nc (netcat) options on Ubuntu vs RedHat

nc -q -1 local host ${PORT} ${CMD} In Ubuntu, nc may be used as above, with the -q option. See manpage. -q after EOF on stdin, wait the specified number of seconds and then quit. If seconds is ...
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How to purge connections left open by SSH ProxyCommand?

I have a webserver WWW1 and a front-facing proxy PRX. I use SSH ProxyCommand to connect to WWW1's internal IP (private IP) via PRX (private+public IP). For some connections (not all) I see a network ...
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How can I pipe commands to a netcat that will stay alive?

echo command | netcat host port This results in the command being sent to the remote host and some data being read back. But after a few seconds, the connection closes. The -w parameter did not ...
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netcat as a multithread server

I use netcat to run a simple server like this: while true; do nc -l -p 2468 -e ./my_exe; done This way, anyone is able to connect to my host on port 2468 and talk with "my_exe". Unfortunately, if ...
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Terminal command to send data (plain text string) to a port at a remote computer

I am trying to send data (plain text string) to a port at a remote computer using terminal utility. The string would be used to trigger something on the remote computer running a program that would ...
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Simple secured SFTP tunnel?

I'd like to setup an sftp tunnel so that I can connect to an IP-secured SFTP server through a gateway computer from anywhere, and download the files to anywhere. I was thinking of using a combination ...
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Bash RTSP client with netcat - keep connection open while parsing sent data with sed?

I am trying to make a RTSP client in bash. Problem is that I must make only one connection to the server through which it will send video frames. I can keep it on one connection up to the point at ...
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Netcat file transfer problem

I have two custom scripts I just wrote to facilitate transferring files between my VPS and my home server. They are both written in bash (short & sweet): To send: #!/bin/bash SENDFILE=$1 PORT=$2 ...
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nc or socat: How to read data from remote:/dev/ttyACM0?

I have a device running at a remote computer on /dev/ttyACM0 Now I want to read that data on my computer. I can connect to it over ssh. Unfortunately I am a nc/socat rookie and no howto covered this. ...
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Netcat on Mac OS X

Is anybody else not able to get nc -lp 8888 working on Mac OS X? Is there another way to get this to work?
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Sending file via netcat

I'm using something like this to send file from one computer to another: To serve file (on computer A): cat something.zip | nc -l -p 1234 To receive file (on computer B): netcat server.ip.here. ...
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Netcat stops listening for UDP traffic

I am using netcat on some Linux machines (see this other question), but seeing some unexpected behavior. Unlike the guide in the accepted answer, I am not using UDP tunneling to do DNS queries. I ...