转贴一个简单的Web服务器:

httpd.erl

?

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%% httpd.erl - MicroHttpd
-module(httpd).
-author("[email protected]").
  
-export([start/0,start/1,start/2,process/2]).
-import(regexp,[split/2]).
  
-define(defPort,8888).
-define(docRoot,"public").
  
start() -> start(?defPort,?docRoot).
start(Port) -> start(Port,?docRoot). 
start(Port,DocRoot) ->
 case gen_tcp:listen(Port, [binary,{packet, 0},{active, false}]) of
  {ok, LSock} -> server_loop(LSock,DocRoot);
   {error, Reason}  -> exit({Port,Reason})
 end.
  
%% main server loop - wait for next connection, spawn child to process it
server_loop(LSock,DocRoot) ->
 case gen_tcp:accept(LSock) of
  {ok, Sock} ->
   spawn(?MODULE,process,[Sock,DocRoot]),
   server_loop(LSock,DocRoot);
  {error, Reason} ->
   exit({accept,Reason})
 end.
  
%% process current connection
process(Sock,DocRoot) ->
 Req = do_recv(Sock),
 {ok,[Cmd|[Name|[Vers|_]]]} = split(Req,"[ \r\n]"),
 FileName = DocRoot ++ Name,
 LogReq = Cmd ++ " " ++ Name ++ " " ++ Vers,
 Resp = case file:read_file(FileName) of
  {ok, Data} ->
   io:format("~p ~p ok~n",[LogReq,FileName]),
   Data;
  {error, Reason} ->
   io:format("~p ~p failed ~p~n",[LogReq,FileName,Reason]),
   error_response(LogReq,file:format_error(Reason))
  end, 
 do_send(Sock,Resp),
 gen_tcp:close(Sock).
  
%% construct HTML for failure message
error_response(LogReq,Reason) ->
 "<html><head><title>Request Failed</title></head><body>\n" ++
 "<h1>Request Failed</h1>\n" ++ "Your request to " ++ LogReq ++
 " failed due to: " ++ Reason ++ "\n</body></html>\n".
  
%% send a line of text to the socket
do_send(Sock,Msg) ->
 case gen_tcp:send(Sock, Msg) of
  ok -> ok;
   {error, Reason} -> exit(Reason)
 end.
  
%% receive data from the socket
do_recv(Sock) ->
 case gen_tcp:recv(Sock, 0) of
  {ok, Bin} -> binary_to_list(Bin);
   {error, closed} -> exit(closed);
   {error, Reason} -> exit(Reason)
 end

运行时在httpd.erl本地建一个public目录,public目录里放一个index.html文件 
然后httpd:start()启动服务器,就可以访问http://localhost:8888/index.html了