創建新進程：spawn
語法：spawn(Module, Exported_Function, List ofArguments).
舉例：spawn(tut14, say_something, [hello, 3]),
發消息：Pid ! Message
舉例：Ping_PID ! pong表示向Ping_PID進程發送元組pong (!操作符用於發消息)
self()：self() returns the pid of the process which executes self()
接收消息：receive ....end
語法：
receive
pattern1 ->
actions1;
pattern2 ->
actions2;
....
patternN
actionsN
end.
接收超時：after
語法：after time
舉例：after 5000(見tut19)
pong() ->
receive
{ping, Ping_PID} ->
io:format("Pong received ping~n", []),
Ping_PID ! pong,
pong()
after 5000 ->
io:format("Pong timed out~n", [])
end.
下面兩個特殊的超時time：
1)infinity(無窮大)，infinity是一個atom，指定了超時設置將永遠不會被執行。
2) 0，超時如果設定爲0意味着超時設置將立刻執行，但是系統將首先嚐試當前“郵箱”裏的消息。
-module(tut14).
-export([start/0, say_something/2]).
say_something(What, 0) ->
done;
say_something(What, Times) ->
io:format("~p~n", [What]),
say_something(What, Times - 1).
start() ->
spawn(tut14, say_something, [hello, 3]),
spawn(tut14, say_something, [goodbye, 3]).
-module(tut15).
-export([start/0, ping/2, pong/0]).
ping(0, Pong_PID) ->
Pong_PID ! finished,
io:format("ping finished~n", []);
ping(N, Pong_PID) ->
Pong_PID ! {ping, self()},
receive
pong ->
io:format("Ping received pong~n", [])
end,
ping(N - 1, Pong_PID).
pong() ->
receive
finished ->
io:format("Pong finished~n", []);
{ping, Ping_PID} ->
io:format("Pong received ping~n", []),
Ping_PID ! pong,
pong()
end.
start() ->
Pong_PID = spawn(tut15, pong, []),
spawn(tut15, ping, [3, Pong_PID]).
-module(tut19).
-export([start_ping/1, start_pong/0, ping/2, pong/0]).
ping(0, Pong_Node) ->
io:format("ping finished~n", []);
ping(N, Pong_Node) ->
{pong, Pong_Node} ! {ping, self()},
receive
pong ->
io:format("Ping received pong~n", [])
end,
ping(N - 1, Pong_Node).
pong() ->
receive
{ping, Ping_PID} ->
io:format("Pong received ping~n", []),
Ping_PID ! pong,
pong()
after 5000 ->
io:format("Pong timed out~n", [])
end.
start_pong() ->
register(pong, spawn(tut19, pong, [])).
start_ping(Pong_Node) ->
spawn(tut19, ping, [3, Pong_Node]).