Netcat ( http://netcat.sourceforge.net/ ) is used in order to write and read over the network…
Computer B read (captures) :
nc -l -p <PORT> (reads from tcp <PORT> and write to <stdout>)
Computer A write (sends):
nc <IP> <PORT> (writes to <IP>:<PORT> what reads from <stdin>)
Since nc can read and write on standard input/output you can use pipe in order to stream data over the network.
Notes :
- netcat is the nc command
- if you want to chain together two computers you have to run first the READ command on B and after WRITE command on A line
#1 Example : Hello World!
print “Hello world!” (over the net)
Computer B read (captures) :
nc -l -p <PORT>
Computer A write (sends):
echo “Hello world!” | nc <IP> <PORT>
Step by Step
1) computer B (192.168.1.3): nc -l -p 8181
computer B remains in listening for something to read from tcp <PORT>
2) computer A: echo ‘hello world!’ | nc 192.168.1.3 8181
computer A writes something to B (192.168.1.3)
3) when execute command on A computer B has something to read … so it shows “hello word!” on stdout
#2 Example : transfer File
Computer B (captures files) :
nc -l -p 8080 | tar -x
Computer A (source of files) :
tar -c . | nc 192.168.1.3 8080
(please check the correct options for your tar)
Sure you can use compression (z option) but you have to keep in mind that this could be a wrong choice. If you are transfering files to a slow computer (for example you telneted a NAS with a slow ARM) the compression could consume too CPU… and copy result very slow. Moreover the bottleneck is not always, and in any case the network (the compression allow to transfer less bytes over the network), … somethime bottleneck is disk or CPU.
#3 Example : cat
Computer B (recieves cat) :
nc -l -p 8181 | more
Computer A (source of cat) :
cat <filename> | nc 192.168.1.3 8181
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