Netcat is a computer networking service for reading from and writing network connections using TCP or UDP

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nc -l in background closes immediately (nc -l 1234 &)

When I put this nc -l 12345 >nc_out in a shell script, run it and then connect from other shell using telnet, it allows me to type some text and have it end up in nc_out. But if I start nc in ...
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Netcat (nc6) - Minimal IPv6 only TCP Server and Client

Im am trying to set up a basic IPv6 only echo-server using netcat (or rather nc6). Client and server are both in the same local network. However, the client quits immediately: IPv6-Server: $ nc6 ...
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Output of one command is piped to another one; how to close both?

I call Qt Assistant like suggested on stackoverflow: nc -lkU ~/.assistantfifo | assistant -enableRemoteControl & Qt Assistant window is opened, and if I call jobs, it returns: [1] + running ...
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Getting more output from NetCat

Currently I'm using the standard netcat -e /bin/sh to provide a remote shell for other computers to access. The problem is however that this shell is rather terrible, since it has limited output. For ...
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nc: bind failed: Address already in use

I am trying to execute nc command from a script , my script is executing nc command on different ports of Destination using the same source port. e.g: nc -p 8140 -z -v -n 10.X.X.9 9090 nc -p 8140 -z ...
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netcat doesn't work as expected when detached from console with nohup (Ubuntu/Debian 64bit)

I'm trying to leave netcat running and close the ssh session (even stop the ssh daemon). But it then exits before all of the data is written. I'm testing in a non-ssh (local) console: nohup nc -l -p ...
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380 views

cat file to udp, pt 2: send 1 udp packet per ^C-delimited line

Yesterday I asked a question about catting a file over a UDP socket in bash. The solution we came up was netcat -c -w 1 -v -u -s 127.0.0.1 239.255.0.1 30001 < test.txt. This worked in the sense ...
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How to avoid sending EOF from a script parsing requests from and sending answers to netcat

I made a simple server using netcat and backpipe: mkfifo backpipe nc -l 8080 < backpipe | parseRequests.sh > backpipe The contents of "parseRequests.sh" is just: #!/bin/sh if [ "$1" = "1+1" ...
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112 views

Log from TCP Port breaking messages on characters other than newline

I'm working on a set of scripts to monitor some external services that log to a TCP port. function handleMessage { while read message do # Handle $message done } nc -d $ipadd $port | ...
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Stream Video using Netcat and VLC

I'm trying to use netcat on Linux server to stream video to my windows client using VLC I started running netcat on Linux: cat /media/HD1/myMovie.mkv | nc -l 8668 In VLC Windows Client I tried ...
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How to copy a partition over network

I want to copy a Windows 7 partition that came installed on my laptop to my desktop computer. I've tried: # bzip2 -c /dev/sda5 | nc 192.168.1.1 2222 # on laptop # nc -l 2222 | bzip2 -d > ...
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Command line streaming string manipulation from netcat

I have a netcat udp connection listening with nc -l -u .... I've been trying to do a per packet manipulation of the incoming data with just command line, but it doesn't look like there is a flag in ...
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convert a hex string to binary and send with netcat

I have a binary file that I can send with netcat: $ nc -l localhost 8181 < my.dat The file contains this: $ xxd my.dat 0000000: 0006 3030 3030 4e43 ..0000NC What I really ...
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Remote desktop over SSH reverse tunnel to replace TeamViewer

I want to open a remote desktop session from my laptop to desktop over my SSH (reverse) tunnel. That should be simple (or at least doable), right? Until now I've been using Team Viewer to log in to ...
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is it possible to send the remote connector ip via netcat?

Actually I want to make something like ifconfig.me functionality but only for my internal network. I see it the way smth on server listens some port and send ip of connected remote machine. Seems nc ...
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1answer
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How to put value of echo pipe netcat commands into variable [duplicate]

I have this command succession: echo -ne "/dev/shm/test.sh" | netcat 89.196.167.2 4567 and let's say it return a string like, for example "Hello...bla". (on the 89.196.167.2 i have made a server ...
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/dev/tcp listen instead of nc listen

With a netcat listener like: nc -l <port> < ~/.bashrc I can grab my .bashrc on a new machine (doesn't have nc or LDAP) with: cat < /dev/tcp/<ip>/<port> > ~/.bashrc My ...
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SSH jumping over socks(4/5) proxy chain. Host -> socks proxy -> socks proxy -> destination

I got a great answer for my previous question about connecting from Machine A to Machine C via Socks proxy located on Machine B. Say Machine B Ip is 218.62.97.105 and it is listening on port 1080 ...
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1answer
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netcat in shell script giving invalid connection

I have a shell script that uses netcat to listen to localhost on port 1111 for web requests. Every time I try accessing localhost:1111/index.html for example I get: invalid connection to [127.0.0.1] ...
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Using in/out named pipes for a TCP connection

I've been fiddling with getting this to work for a while now, so I suspect some sort of fundamental misunderstanding about how pipes work is the root cause of my troubles. My goal is to initiate a ...
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Servers running from chrooted Ubuntu on HP TouchPad? [closed]

The problem: servers appear to be broken inside my Ubuntu chroot. No matter what kind of server I try to run, they all seem unresponsive (VLC server won't respond to client, mkRemote doesn't move the ...
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3answers
606 views

How can I read lines at a fixed speed?

I need to read a large log file and send it over a local network using (netbsd) netcat between two VMs on the same host workstation. I know that netcat has an interval, but as far as I can tell, the ...
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How to make netcat use an existing HTTP proxy

I can access a web page just fine by directly hitting my web server as follows: $ echo "GET /sample" | nc web-server 80 This is contents of /sample... $ Now, I would like netcat to go via a Squid ...
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Different redirection styles with netcat and tee giving different results

In trying to trace a simple HTTP GET request and its response with nc, I'm running into something strange. This, for example, works fine: the in file ends up containing the HTTP GET request and the ...
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Why does this shell snippet to check if hosts are up using netcat stop prematurely?

Q: Why does the second iteration exits after 10.175.192.16? Can someone explain that? Or I just found a "while/netcat" bug? a.txt's content: $ cat a.txt 10.175.192.14 10.175.192.16 10.175.192.17 $ ...
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netcat throughput low but iperf high [closed]

I was testing the throughput between two pcs connected on the same router: one with 100mbps lan, the other with 54mbps wifi. I tested both netcat and iperf and the throughtput I get is only 2.6mb/s. ...
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Howto create a permanent client connection with netcat?

I'm writing a bash script that constantly read a folder in a loop to send data to a server at a defined time interval. I'm using netcat as the tool to connect to the server and send the data. My ...