Using TCP
We’ll start our adventures in socket programming by looking at a simple TCP program that fetches data from a server. After this, we’ll write a simple sequential TCP server and show how it can be parallelized to handle multiple parallel sessions.
Fetching Data from a Server
Let’s start by writing a little function called nano_get_url/0
that uses a TCP socket
to fetch an HTML page from http://www.google.com.
| socket_examples.erl | |
| | nano_get_url() -> |
| | nano_get_url("www.google.com"). |
| | |
| | nano_get_url(Host) -> |
| ① | {ok,Socket} = gen_tcp:connect(Host,80,[binary, {packet, 0}]), |
| ② | ok = gen_tcp:send(Socket, "GET / HTTP/1.0\r\n\r\n"), |
| | receive_data(Socket, []). |
| | |
| | receive_data(Socket, SoFar) -> |
| | receive |
| ③ | {tcp,Socket,Bin} -> |
| | |
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