1、啟動
方式一：啟動inets應用，一個缺省profile的管理進程將被啟動。
inets:start().
方式二：運行時，動態啟動profile停止profile。
動態啟動profile：
{ok, Pid} = inets:start(httpc, [{profile, foo}]).
動態停止profile：
inets:stop(httpc, foo).
或
inets:stop(httpc, Pid).
2、設置
httpc:set_options() -> ok | {error, Reason}
參考：http://www.erlang.org/doc/man/httpc.html#set_options-1
3、請求
參考：http://www.erlang.org/doc/man/httpc.html#request-1
同步請求：
{ok, {{Version, 200, ReasonPhrase}, Headers, Body}} = httpc:request("http://www.baidu.com").
等同於
{ok, {{Version, 200, ReasonPhrase}, Headers, Body}} = httpc:request(get, {"http://www.baidu.com", []}, [], []).
異步請求：
{ok, RequestId} = httpc:request(get, {"http://www.baidu.com", []}, [], [{sync, false}]),
receive {http, {RequestId, Result}} -> ok after 500 -> error end.