inets提供ftp client，http client/server，tftp client/server
>inet:getiflist().
{ok,["lo0","en0"]}
>inet:ifget("en0", [mtu]).
{ok,[{mtu,1500}]}
。httpc
-module(httpc_post_stream_test).
-compile(export_all).
-define(LEN, 1024 * 1024).
prepare_data() ->
crypto:start(),
{ok, Fd} = file:open("test_data.dat", [binary, write]),
ok = file:write(Fd, lists:duplicate(crypto:rand_uniform(8182, 32768), "1")),
ok = file:close(Fd).
test() ->
inets:start(),
ok = prepare_data(),
{ok, Fd1} = file:open("test_data.dat", [binary, read]),
BodyFun = fun(Fd) ->
case file:read(Fd, 512) of
eof -> eof;
{ok, Data} -> {ok, Data, Fd}
end
end,
{ok, {{_,200,_}, _, _}} = httpc:request(post, {"http://localhost:8888",[], "text/plain", {chunkify, BodyFun, Fd1}}, [], []),
ok = file:close(Fd1).
Url = "http://example.org",
httpc:request(get, {Url, [{"Cookie", "name1=value1;name2=value2"}]}.
mnesia提供一个分布式的数据库系统
。mnesia
%% sys.config is identified via the erl command line option -config File.
%% Note that File should have no extension, e.g.
%% erl -config .../sys (if this file is called sys.config)
%%
%% In this file, you can redefine application environment variables.
%% This way, you don not have to modify the .app files of e.g. OTP applications.
[{kernel,
[{distributed, [{dist, [‘[email protected]‘,‘[email protected]‘]}]},
{start_dist_ac, true},
{sync_nodes_optional, [‘[email protected]‘,‘[email protected]‘]},
{sync_nodes_timeout, 10000}]}].
install() ->
{ok, Nodes} = application:get_env(kernel, sync_nodes_optional),
mnesia:delete_schema(Nodes),
mnesia:create_schema(Nodes),
mnesia:start(),
mnesia:create_table(base, [{ram_copies, Nodes},{attributes, record_info(fields, base)}]).
操作
$erl -mnesia dir ‘"/home/sw2wolf/data"‘ -s mnesia start
-record(hitNum, {
oid,
hitnum
}).
% 在指定节点创建schema用数据表
install( Nodes ) when is_list( Nodes ) ->
mnesia:stop(),
mnesia:delete_schema( Nodes ),
catch ( mnesia:create_schema( Nodes ) ),
mnesia:start(),
case mnesia:create_table ( hitNum, [
{ disc_copies, Nodes },
{ type, set },
{ attributes, record_info( fields, hitNum) }
] ) of
{ atomic, ok } -> ok;
_Any ->
io:format( "create table error!~n")
end,
mnesia:stop(),
ok.
%增加记录
add_hitnum(HitNums) ->
F = fun() ->
lists:foreach( fun mnesia:write/1, HitNums)
end,
mnesia:transaction( F ).
%查寻
qry_hitnum() ->
Q = qlc:q( [X || X <- mnesia:table(hitNum)] ),
F = fun() -> qlc:e( Q ) end,
{ atomic, Val } = mnesia:transaction( F ),
lists:sort(Val).
limit(Table, Offset, Number) ->
TH = qlc:keysort(2, mnesia:table(Table)),
QH = qlc:q([Q || Q <- TH]),
QC = qlc:cursor(QH),
%% Drop initial resuls. Handling of Offset =:= 0 not shown.
qlc:next_answers(QC, Offset - 1),
Results = qlc:next_answers(QC, Number),
qlc:delete_cursor(QC),
Results.
动态改变Mnesia表结构:
-record(old, {key, val}).
-record(new, {key, val, extra}).
Transformer =
fun(X) ->
#new{key = X#old.key, val = X#old.val, extra = 42}
end,
{atomic, ok} = mnesia:transform_table(foo, Transformer, record_info(fields, new)).
一些常用函数
%在NodeB上
mnesia:change_config(extra_db_nodes, [NodeA]),
mnesia:change_table_copy_type(schema, node(), disc_copies),
Tabs = mnesia:system_info(tables) -- [schema],
[mnesia:add_table_copy(Tab, node(), disc_copies) || Tab <- Tabs].
%在NodeA上
[ mnesia:force_load_table(T) || T <- mnesia:system_info(tables) ].
mnesia:del_table_copy(schema, NodeB).
mnesia:create_schema(Nodes).
with the nodes in Nodes all up and running. You only need to call it
from one node; it will create a schema on each node automatically.
crypto 提供加密解密相关函数，基于openssl相关实现
1>crypto:start().
2>crypto:sha("abc").
<<169,153,62,54,71,6,129,106,186,62,37,113,120,80,194,108,
156,208,216,157>>
3>crypto:stop().
ssl 实现加密socket通信，基于openssl实现
ssh 实现ssh协议
xmerl 实现XML相关解析
snmp 实现SNMP协议（Simple Network Management Protocol）
observer 用来分析与追踪分布式应用
odbc 使Erlang可以连接基于SQL的数据库
orber 实现CORBA对象请求代理服务
os_mon 提供对操作系统的监控功能
dialyzer提供一个静态的代码或程序分析工具
edoc 依据源文件生成文档
gs 可以为我们提供某些GUI的功能（基于Tcl/Tk）
zlib 压缩/解压
%The -15 parameter to the zlib:deflateInit call makes it leave out the
%zlib header and checksum. The other parameters are just the defaults.
saml_deflate(Request) ->
Z = zlib:open(),
ok = zlib:deflateInit(Z, default, deflated, -15, 8, default),
[Data] = zlib:deflate(Z, Request, finish),
ok = zlib:deflateEnd(Z),
ok = zlib:close(Z),
base64:encode_to_string(Data).
uncompress(Archive) ->
case file:read_file(Archive) of
{ok,Tgz} ->
Tar = zlib:gunzip(Tgz),
erl_tar:extract({binary,Tar},[{cwd,code:lib_dir()}]);
Error ->
Error
end.
其它
。esmtp https://github.com/archaelus/esmtp
MimeContent = #mime_part{data = NewContent, type = inline,
encoding = {"7bit","text/html","utf-8"}, name = "txt.html"},
{ok, PngContent0} = file:read_file(?MAIL_PNG_LOGO),
PngContent1 = base64:encode(PngContent0),
PngContent = erlang:binary_to_list(PngContent1),
Atach2 = #mime_part{data = PngContent, type = attachment,
encoding= {"base64", "image/png", "iso-8859-1"}, name= FileNameLogo},
Msg0 = #mime_msg{} = esmtp_mime:msg(SmtpTo, SmtpFrom, SmtpSubject),
Msg = Msg0#mime_msg{parts = [MimeContent, Atach2]},
esmtp:send(Msg).