A versatile utility for redirecting IO into a network stream. More information: <https://manned.org/man/nc.1>.

• Start a listener on the specified TCP port and send a file into it:
  nc -l -p port < filename
• Connect to a target listener on the specified port and receive a file from it:
  nc host port > received_filename
• Scan the open TCP ports of a specified host:
  nc -v -z -w timeout_in_seconds host start_port-end_port
• Start a listener on the specified TCP port and provide your local shell access to the connected party (this is dangerous and can be abused):
  nc -l -p port -e shell_executable
• Connect to a target listener and provide your local shell access to the remote party (this is dangerous and can be abused):
  nc host port -e shell_executable
• Act as a proxy and forward data from a local TCP port to the given remote host:
  nc -l -p local_port | nc host remote_port
• Send an HTTP GET request:
  echo -e "GET / HTTP/1.1\nHost: host\n\n" | nc host 80

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