anchor.diff:  # $json
   ....
   
  -5. Show response and close connection.
  +`5.` Show response and close connection.
   ....
    cat <&3
    exec 3<&-
  
positive.code: )
  ....
  
  2. Calculate Content-Length.
  ....
   len=${#json}
  ....
  
  3. Open TCP socket using descriptor (3).
  ....
  #exec 3<>/dev/tcp/SERVER/PORT
   exec 3<>/dev/tcp/some.server/8080
  ....
  
  4. ECHO spoofed header to descriptor (3).
  ....
  #This must be on 1 line.
   echo -e "POST /URI/TO/RESTful/API HTTP/1.1\r\nHost: some.server\r\nContent-type: application/json\r\nContent-length: $len\r\nConnection: close \r\n\r\n$json">&3
  
negative.code: // See https://hubpress.gitbooks.io/hubpress-knowledgebase/content/ for information about the parameters.
  // :hp-image: /covers/cover.png
  // :published_at: 2019-01-31
  :hp-tags: Linux, Unix, REST, CLI, BASH
  // :hp-alt-title: My English Title
  
  If your REST URL looks like this:
  ....
   http://some.server:8080/URI/TO/RESTful/API
  ....
  
  `1.` Construct your JSON variable.
  ....
  #No indentations otherwise heredoc may break.
  json=$(cat <<EOF
  