Merge branch 'hb/specs_and_types/OTP-9356' into dev

* hb/specs_and_types/OTP-9356:
  Add more specs and types

4 files changed, 280 insertions, 86 deletions

diff --git a/erts/preloaded/src/erl_prim_loader.erl b/erts/preloaded/src/erl_prim_loader.erl
index 024b20eadb..ccfa7978c8 100644
--- a/erts/preloaded/src/erl_prim_loader.erl
+++ b/erts/preloaded/src/erl_prim_loader.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -102,8 +102,14 @@ debug(#prim_state{debug = Deb}, Term) ->
 %%% Interface Functions. 
 %%% --------------------------------------------------------
 
--spec start(term(), atom() | string(), host() | [host()]) ->
-	    {'ok', pid()} | {'error', term()}.
+-spec start(Id, Loader, Hosts) ->
+	    {'ok', Pid} | {'error', What} when
+      Id :: term(),
+      Loader :: atom() | string(),
+      Hosts :: Host | [Host],
+      Host :: host(),
+      Pid :: pid(),
+      What :: term().
 start(Id, Pgm, Hosts) when is_atom(Hosts) ->
     start(Id, Pgm, [Hosts]);
 start(Id, Pgm0, Hosts) ->
@@ -123,18 +129,6 @@ start(Id, Pgm0, Hosts) ->
             {error,Reason}
     end.
 
-start_it("ose_inet"=Cmd, Id, Pid, Hosts) ->
-    %% Setup reserved port for ose_inet driver (only OSE)
-    case catch erlang:open_port({spawn,Cmd}, [binary]) of
-        {'EXIT',Why} ->
-            ?dbg(ose_inet_port_open_fail, Why),
-            Why;
-        OseInetPort ->
-            ?dbg(ose_inet_port, OseInetPort),
-            OseInetPort
-    end,
-    start_it("inet", Id, Pid, Hosts);
-
 %% Hosts must be a list on form ['1.2.3.4' ...]
 start_it("inet", Id, Pid, Hosts) ->
     process_flag(trap_exit, true),
@@ -174,15 +168,20 @@ init_ack(Pid) ->
     Pid ! {self(),ok},
     ok.
 
--spec set_path([string()]) -> 'ok'.
+-spec set_path(Path) -> 'ok' when
+      Path :: [Dir :: string()].
 set_path(Paths) when is_list(Paths) ->
     request({set_path,Paths}).
 
--spec get_path() -> {'ok', [string()]}.
+-spec get_path() -> {'ok', Path} when
+      Path :: [Dir :: string()].
 get_path() ->
     request({get_path,[]}).
 
--spec get_file(atom() | string()) -> {'ok', binary(), string()} | 'error'.
+-spec get_file(Filename) -> {'ok', Bin, FullName} | 'error' when
+      Filename :: atom() | string(),
+      Bin :: binary(),
+      FullName :: string().
 get_file(File) when is_atom(File) ->
     get_file(atom_to_list(File));
 get_file(File) ->
@@ -202,13 +201,15 @@ get_files(ModFiles, Fun) ->
             ok
     end.
 
--spec list_dir(string()) -> {'ok', [string()]} | 'error'.
+-spec list_dir(Dir) -> {'ok', Filenames} | 'error' when
+      Dir :: string(),
+      Filenames :: [Filename :: string()].
 list_dir(Dir) ->
     check_file_result(list_dir, Dir, request({list_dir,Dir})).
 
-%% -> {ok,Info} | error
--spec read_file_info(string()) -> {'ok', tuple()} | 'error'.
-
+-spec read_file_info(Filename) -> {'ok', FileInfo} | 'error' when
+      Filename :: string(),
+      FileInfo :: file:file_info().
 read_file_info(File) ->
     check_file_result(read_file_info, File, request({read_file_info,File})).
 
@@ -1360,9 +1361,7 @@ pathtype(Name) when is_list(Name) ->
 		    absolute;
 		_ ->
 		    relative
-	    end;
-	{ose,_} ->
-	    unix_pathtype(Name)
+	    end
     end.
 
 unix_pathtype(Name) ->
diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index 4679a916c7..5deb69edab 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -53,22 +53,31 @@
 -compile({no_auto_import,[spawn_opt/4]}).
 -compile({no_auto_import,[spawn_opt/5]}).
 
-%%--------------------------------------------------------------------------
+-export_type([timestamp/0]).
 
--type date() :: {pos_integer(), pos_integer(), pos_integer()}.
--type time() :: {non_neg_integer(), non_neg_integer(), non_neg_integer()}.
--type date_time() :: {date(), time()}.
+-type timestamp() :: {MegaSecs :: non_neg_integer(),
+                      Secs :: non_neg_integer(),
+                      MicroSecs :: non_neg_integer()}.
 
 %%--------------------------------------------------------------------------
 
+-spec apply(Fun, Args) -> term() when
+      Fun :: function(),
+      Args :: [term()].
 apply(Fun, Args) ->
     erlang:apply(Fun, Args).
 
+-spec apply(Module, Function, Args) -> term() when
+      Module :: module(),
+      Function :: atom(),
+      Args :: [term()].
 apply(Mod, Name, Args) ->
     erlang:apply(Mod, Name, Args).
 
 %% Spawns with a fun
 
+-spec spawn(Fun) -> pid() when
+      Fun :: function().
 spawn(F) when is_function(F) ->
     spawn(erlang, apply, [F, []]);
 spawn({M,F}=MF) when is_atom(M), is_atom(F) ->
@@ -76,6 +85,9 @@ spawn({M,F}=MF) when is_atom(M), is_atom(F) ->
 spawn(F) ->
     erlang:error(badarg, [F]).
 
+-spec spawn(Node, Fun) -> pid() when
+      Node :: node(),
+      Fun :: function().
 spawn(N, F) when N =:= node() ->
     spawn(F);
 spawn(N, F) when is_function(F) ->
@@ -85,6 +97,8 @@ spawn(N, {M,F}=MF) when is_atom(M), is_atom(F) ->
 spawn(N, F) ->
     erlang:error(badarg, [N, F]).
 
+-spec spawn_link(Fun) -> pid() when
+      Fun :: function().
 spawn_link(F) when is_function(F) ->
     spawn_link(erlang, apply, [F, []]);
 spawn_link({M,F}=MF) when is_atom(M), is_atom(F) ->
@@ -92,6 +106,9 @@ spawn_link({M,F}=MF) when is_atom(M), is_atom(F) ->
 spawn_link(F) ->
     erlang:error(badarg, [F]).
 
+-spec spawn_link(Node, Fun) -> pid() when
+      Node :: node(),
+      Fun :: function().
 spawn_link(N, F) when N =:= node() ->
     spawn_link(F);
 spawn_link(N, F) when is_function(F) ->
@@ -103,16 +120,30 @@ spawn_link(N, F) ->
 
 %% Spawn and atomically set up a monitor.
 
+-spec spawn_monitor(Fun) -> {pid(), reference()} when
+      Fun :: function().
 spawn_monitor(F) when is_function(F, 0) ->
     erlang:spawn_opt({erlang,apply,[F,[]],[monitor]});
 spawn_monitor(F) ->
     erlang:error(badarg, [F]).
 
+-spec spawn_monitor(Module, Function, Args) -> {pid(), reference()} when
+      Module :: module(),
+      Function :: atom(),
+      Args :: [term()].
 spawn_monitor(M, F, A) when is_atom(M), is_atom(F), is_list(A) ->
     erlang:spawn_opt({M,F,A,[monitor]});
 spawn_monitor(M, F, A) ->
     erlang:error(badarg, [M,F,A]).
 
+-spec spawn_opt(Fun, Options) -> pid() | {pid(), reference()} when
+      Fun :: function(),
+      Options :: [Option],
+      Option :: link | monitor | {priority, Level}
+              | {fullsweep_after, Number :: non_neg_integer()}
+              | {min_heap_size, Size :: non_neg_integer()}
+              | {min_bin_vheap_size, VSize :: non_neg_integer()},
+      Level :: low | normal | high.
 spawn_opt(F, O) when is_function(F) ->
     spawn_opt(erlang, apply, [F, []], O);
 spawn_opt({M,F}=MF, O) when is_atom(M), is_atom(F) ->
@@ -122,6 +153,15 @@ spawn_opt({M,F,A}, O) -> % For (undocumented) backward compatibility
 spawn_opt(F, O) ->
     erlang:error(badarg, [F, O]).
 
+-spec spawn_opt(Node, Fun, Options) -> pid() | {pid(), reference()} when
+      Node :: node(),
+      Fun :: function(),
+      Options :: [Option],
+      Option :: link | monitor | {priority, Level}
+              | {fullsweep_after, Number :: non_neg_integer()}
+              | {min_heap_size, Size :: non_neg_integer()}
+              | {min_bin_vheap_size, VSize :: non_neg_integer()},
+      Level :: low | normal | high.
 spawn_opt(N, F, O) when N =:= node() ->
     spawn_opt(F, O);
 spawn_opt(N, F, O) when is_function(F) ->
@@ -133,6 +173,11 @@ spawn_opt(N, F, O) ->
 
 %% Spawns with MFA
 
+-spec spawn(Node, Module, Function, Args) -> pid() when
+      Node :: node(),
+      Module :: module(),
+      Function :: atom(),
+      Args :: [term()].
 spawn(N,M,F,A) when N =:= node(), is_atom(M), is_atom(F), is_list(A) ->
     spawn(M,F,A);
 spawn(N,M,F,A) when is_atom(N), is_atom(M), is_atom(F) ->
@@ -158,6 +203,11 @@ spawn(N,M,F,A) when is_atom(N), is_atom(M), is_atom(F) ->
 spawn(N,M,F,A) ->
     erlang:error(badarg, [N, M, F, A]).
 
+-spec spawn_link(Node, Module, Function, Args) -> pid() when
+      Node :: node(),
+      Module :: module(),
+      Function :: atom(),
+      Args :: [term()].
 spawn_link(N,M,F,A) when N =:= node(), is_atom(M), is_atom(F), is_list(A) ->
     spawn_link(M,F,A);
 spawn_link(N,M,F,A) when is_atom(N), is_atom(M), is_atom(F) ->
@@ -183,6 +233,17 @@ spawn_link(N,M,F,A) when is_atom(N), is_atom(M), is_atom(F) ->
 spawn_link(N,M,F,A) ->
     erlang:error(badarg, [N, M, F, A]).
 
+-spec spawn_opt(Module, Function, Args, Options) ->
+                       pid() | {pid(), reference()} when
+      Module :: module(),
+      Function :: atom(),
+      Args :: [term()],
+      Options :: [Option],
+      Option :: link | monitor | {priority, Level}
+              | {fullsweep_after, Number :: non_neg_integer()}
+              | {min_heap_size, Size :: non_neg_integer()}
+              | {min_bin_vheap_size, VSize :: non_neg_integer()},
+      Level :: low | normal | high.
 spawn_opt(M, F, A, Opts) ->
     case catch erlang:spawn_opt({M,F,A,Opts}) of
 	{'EXIT',{Reason,_}} ->
@@ -191,6 +252,18 @@ spawn_opt(M, F, A, Opts) ->
 	    Res
     end.
 
+-spec spawn_opt(Node, Module, Function, Args, Options) ->
+                       pid() | {pid(), reference()} when
+      Node :: node(),
+      Module :: module(),
+      Function :: atom(),
+      Args :: [term()],
+      Options :: [Option],
+      Option :: link | monitor | {priority, Level}
+              | {fullsweep_after, Number :: non_neg_integer()}
+              | {min_heap_size, Size :: non_neg_integer()}
+              | {min_bin_vheap_size, VSize :: non_neg_integer()},
+      Level :: low | normal | high.
 spawn_opt(N, M, F, A, O) when N =:= node(),
 			      is_atom(M), is_atom(F), is_list(A),
 			      is_list(O) ->
@@ -260,18 +333,25 @@ crasher(Node,Mod,Fun,Args,Opts,Reason) ->
 			     [Mod,Fun,Args,Opts,Node]),
     exit(Reason).
 
--spec yield() -> 'true'.
+-spec erlang:yield() -> 'true'.
 yield() ->
     erlang:yield().
 
--spec nodes() -> [node()].
+-spec nodes() -> Nodes when
+      Nodes :: [node()].
 nodes() ->
     erlang:nodes(visible).
 
--spec disconnect_node(node()) -> boolean().
+-spec disconnect_node(Node) -> boolean() | ignored when
+      Node :: node().
 disconnect_node(Node) ->
     net_kernel:disconnect(Node).
 
+-spec erlang:fun_info(Fun) -> [{Item, Info}] when
+      Fun :: function(),
+      Item :: arity | env | index | name
+            | module | new_index | new_uniq | pid | type | uniq,
+      Info :: term().
 fun_info(Fun) when is_function(Fun) ->
     Keys = [type,env,arity,name,uniq,index,new_uniq,new_index,module,pid],
     fun_info_1(Keys, Fun, []).
@@ -283,24 +363,37 @@ fun_info_1([K|Ks], Fun, A) ->
     end;
 fun_info_1([], _, A) -> A.
 
--type dst() :: pid() | port() | atom() | {atom(), node()}.
+-type dst() :: pid()
+             | port()
+             | (RegName :: atom())
+             | {RegName :: atom(), Node :: node()}.
 
--spec send_nosuspend(dst(), term()) -> boolean().
+-spec erlang:send_nosuspend(Dest, Msg) -> boolean() when
+      Dest :: dst(),
+      Msg :: term().
 send_nosuspend(Pid, Msg) ->
     send_nosuspend(Pid, Msg, []).
 
--spec send_nosuspend(dst(), term(), ['noconnect' | 'nosuspend']) -> boolean().
+-spec erlang:send_nosuspend(Dest, Msg, Options) -> boolean() when
+      Dest :: dst(),
+      Msg :: term(),
+      Options :: [noconnect].
 send_nosuspend(Pid, Msg, Opts) ->
     case erlang:send(Pid, Msg, [nosuspend|Opts]) of
 	ok -> true;
 	_  -> false
     end.
 
--spec localtime_to_universaltime(date_time()) -> date_time().
+-spec erlang:localtime_to_universaltime({Date1, Time1}) -> {Date2, Time2} when
+      Date1 :: calendar:date(),
+      Date2 :: calendar:date(),
+      Time1 :: calendar:time(),
+      Time2 :: calendar:time().
 localtime_to_universaltime(Localtime) ->
     erlang:localtime_to_universaltime(Localtime, undefined).
 
--spec suspend_process(pid()) -> 'true'.
+-spec erlang:suspend_process(Suspendee) -> 'true' when
+      Suspendee :: pid().
 suspend_process(P) ->
     case catch erlang:suspend_process(P, []) of
 	{'EXIT', {Reason, _}} -> erlang:error(Reason, [P]);
@@ -426,6 +519,9 @@ delay_trap(Result, Timeout) -> receive after Timeout -> Result end.
 %% Messages to us use our cookie. IF we change our cookie, other nodes 
 %% have to reflect that, which we cannot forsee.
 %%
+-spec erlang:set_cookie(Node, Cookie) -> true when
+      Node :: node(),
+      Cookie :: atom().
 set_cookie(Node, C) when Node =/= nonode@nohost, is_atom(Node) ->
     case is_atom(C) of
 	true ->
@@ -434,14 +530,19 @@ set_cookie(Node, C) when Node =/= nonode@nohost, is_atom(Node) ->
 	    error(badarg)
     end.
 
--spec get_cookie() -> atom().
+-spec erlang:get_cookie() -> Cookie | nocookie when
+      Cookie :: atom().
 get_cookie() ->
     auth:get_cookie().
 
+-spec concat_binary(ListOfBinaries) -> binary() when
+      ListOfBinaries :: iolist().
 concat_binary(List) ->
     list_to_binary(List).
 
--spec integer_to_list(integer(), 1..255) -> string().
+-spec integer_to_list(Integer, Base) -> string() when
+      Integer :: integer(),
+      Base :: 2..36.
 integer_to_list(I, 10) ->
     erlang:integer_to_list(I);
 integer_to_list(I, Base) 
@@ -469,6 +570,9 @@ integer_to_list(I0, Base, R0) ->
     end.
 
 
+-spec list_to_integer(String, Base) -> integer() when
+      String :: string(),
+      Base :: 2..36.
 list_to_integer(L, 10) ->
     erlang:list_to_integer(L);
 list_to_integer(L, Base)
@@ -689,10 +793,16 @@ await_proc_exit(Proc, Op, Data) ->
 	    end
     end.
 
--spec min(term(), term()) -> term().
+-spec min(Term1, Term2) -> Minimum when
+      Term1 :: term(),
+      Term2 :: term(),
+      Minimum :: term().
 min(A, B) when A > B -> B;
 min(A, _) -> A.
 
--spec max(term(), term()) -> term().
+-spec max(Term1, Term2) -> Maximum when
+      Term1 :: term(),
+      Term2 :: term(),
+      Maximum :: term().
 max(A, B) when A < B -> B;
 max(A, _) -> A.
diff --git a/erts/preloaded/src/init.erl b/erts/preloaded/src/init.erl
index 24430a3d40..e52c813029 100644
--- a/erts/preloaded/src/init.erl
+++ b/erts/preloaded/src/init.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -28,10 +28,10 @@
 %%                       : $Var in the boot script is expanded to
 %%                         Value.
 %%        -loader LoaderMethod
-%%                       : efile, inet, ose_inet
+%%                       : efile, inet
 %%                         (Optional - default efile)
 %%        -hosts [Node]  : List of hosts from which we can boot.
-%%                         (Mandatory if -loader inet or ose_inet)
+%%                         (Mandatory if -loader inet)
 %%        -mode embedded : Load all modules at startup, no automatic loading
 %%        -mode interactive : Auto load modules (default system behaviour).
 %%        -path          : Override path in bootfile.
@@ -79,19 +79,24 @@
 debug(false, _) -> ok;
 debug(_, T)     -> erlang:display(T).
 
--spec get_arguments() -> [{atom(), [string()]}].
+-spec get_arguments() -> Flags when
+      Flags :: [{Flag :: atom(), Values :: [string()]}].
 get_arguments() ->
     request(get_arguments).
 
--spec get_plain_arguments() -> [string()].
+-spec get_plain_arguments() -> [Arg] when
+      Arg :: string().
 get_plain_arguments() ->
     bs2ss(request(get_plain_arguments)).
 
--spec get_argument(atom()) -> 'error' | {'ok', [[string()]]}.
+-spec get_argument(Flag) -> {'ok', Arg} | 'error' when
+      Flag :: atom(),
+      Arg :: [Values :: [string()]].
 get_argument(Arg) ->
     request({get_argument, Arg}).
 
--spec script_id() -> term().
+-spec script_id() -> Id when
+      Id :: term().
 script_id() ->
     request(script_id).
 
@@ -105,7 +110,9 @@ bs2ss(L0) when is_list(L0) ->
 bs2ss(L) ->
     L.
 
--spec get_status() -> {internal_status(), term()}.
+-spec get_status() -> {InternalStatus, ProvidedStatus} when
+      InternalStatus :: internal_status(),
+      ProvidedStatus :: term().
 get_status() ->
     request(get_status).
 
@@ -150,10 +157,12 @@ reboot() -> init ! {stop,reboot}, ok.
 -spec stop() -> 'ok'.
 stop() -> init ! {stop,stop}, ok.
 
--spec stop(non_neg_integer() | string()) -> 'ok'.
+-spec stop(Status) -> 'ok' when
+      Status :: non_neg_integer() | string().
 stop(Status) -> init ! {stop,{stop,Status}}, ok.
 
--spec boot([binary()]) -> no_return().
+-spec boot(BootArgs) -> no_return() when
+      BootArgs :: [binary()].
 boot(BootArgs) ->
     register(init, self()),
     process_flag(trap_exit, true),
@@ -1024,7 +1033,7 @@ start_it({eval,Bin}) ->
 	      TsR -> reverse([{dot,1} | TsR])
 	  end,
     {ok,Expr} = erl_parse:parse_exprs(Ts1),
-    erl_eval:exprs(Expr, []),
+    erl_eval:exprs(Expr, erl_eval:new_bindings()),
     ok;
 start_it([_|_]=MFA) ->
     Ref = make_ref(),
diff --git a/erts/preloaded/src/zlib.erl b/erts/preloaded/src/zlib.erl
index 51d6cd0a0b..6cc7b27114 100644
--- a/erts/preloaded/src/zlib.erl
+++ b/erts/preloaded/src/zlib.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2003-2010. All Rights Reserved.
+%% Copyright Ericsson AB 2003-2011. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -124,7 +124,6 @@
 -type zwindowbits() :: -15..-9 | 9..47.
 -type zmemlevel()   :: 1..9.
 -type zstrategy()   :: 'default' | 'filtered' | 'huffman_only'.
--type zflush()      :: 'none' | 'sync' | 'full' | 'finish'.
 
 %%------------------------------------------------------------------------
 
@@ -134,7 +133,8 @@ open() ->
     open_port({spawn, "zlib_drv"}, [binary]).
 
 %% close and release z_stream
--spec close(zstream()) -> 'ok'.
+-spec close(Z) -> 'ok' when
+      Z :: zstream().
 close(Z) ->
     try
 	true = port_close(Z),
@@ -145,16 +145,25 @@ close(Z) ->
     catch _:_ -> erlang:error(badarg)
     end.
 
--spec deflateInit(zstream()) -> 'ok'.
+-spec deflateInit(Z) -> 'ok' when
+      Z :: zstream().
 deflateInit(Z) ->
     call(Z, ?DEFLATE_INIT, <<?Z_DEFAULT_COMPRESSION:32>>).
 
--spec deflateInit(zstream(), zlevel()) -> 'ok'.
+-spec deflateInit(Z, Level) -> 'ok' when
+      Z :: zstream(),
+      Level :: zlevel().
 deflateInit(Z, Level) ->
     call(Z, ?DEFLATE_INIT, <<(arg_level(Level)):32>>).
 
--spec deflateInit(zstream(), zlevel(), zmethod(),
-		  zwindowbits(), zmemlevel(), zstrategy()) -> 'ok'.
+-spec deflateInit(Z, Level, Method,
+		  WindowBits, MemLevel, Strategy) -> 'ok' when
+      Z :: zstream(),
+      Level :: zlevel(),
+      Method :: zmethod(),
+      WindowBits :: zwindowbits(),
+      MemLevel :: zmemlevel(),
+      Strategy :: zstrategy().
 deflateInit(Z, Level, Method, WindowBits, MemLevel, Strategy) ->
     call(Z, ?DEFLATE_INIT2, <<(arg_level(Level)):32, 
 			     (arg_method(Method)):32,
@@ -162,24 +171,38 @@ deflateInit(Z, Level, Method, WindowBits, MemLevel, Strategy) ->
 			     (arg_mem(MemLevel)):32,
 			     (arg_strategy(Strategy)):32>>).
 
--spec deflateSetDictionary(zstream(), binary()) -> integer().
+-spec deflateSetDictionary(Z, Dictionary) -> Adler32 when
+      Z :: zstream(),
+      Dictionary :: binary(),
+      Adler32 :: integer().
 deflateSetDictionary(Z, Dictionary) ->
     call(Z, ?DEFLATE_SETDICT, Dictionary).
 
--spec deflateReset(zstream()) -> 'ok'.
+-spec deflateReset(Z) -> 'ok' when
+      Z :: zstream().
 deflateReset(Z) ->
     call(Z, ?DEFLATE_RESET, []).
 
--spec deflateParams(zstream(), zlevel(), zstrategy()) -> 'ok'.
+-spec deflateParams(Z, Level, Strategy) -> ok when
+      Z :: zstream(),
+      Level :: zlevel(),
+      Strategy :: zstrategy().
 deflateParams(Z, Level, Strategy) ->
     call(Z, ?DEFLATE_PARAMS, <<(arg_level(Level)):32, 
 			      (arg_strategy(Strategy)):32>>).
 
--spec deflate(zstream(), iodata()) -> iolist().
+-spec deflate(Z, Data) -> Compressed when
+      Z :: zstream(),
+      Data :: iodata(),
+      Compressed :: iolist().
 deflate(Z, Data) ->
     deflate(Z, Data, none).
 
--spec deflate(zstream(), iodata(), zflush()) -> iolist().
+-spec deflate(Z, Data, Flush) -> Compressed when
+      Z :: zstream(),
+      Data :: iodata(),
+      Flush :: none | sync | full | finish,
+      Compressed :: iolist().
 deflate(Z, Data, Flush) ->
     try port_command(Z, Data) of
 	true ->
@@ -191,19 +214,25 @@ deflate(Z, Data, Flush) ->
 	    erlang:error(badarg) 
     end.
 
--spec deflateEnd(zstream()) -> 'ok'.
+-spec deflateEnd(Z) -> 'ok' when
+      Z :: zstream().
 deflateEnd(Z) ->
     call(Z, ?DEFLATE_END, []).    
 
--spec inflateInit(zstream()) -> 'ok'.
+-spec inflateInit(Z) -> 'ok' when
+      Z :: zstream().
 inflateInit(Z) ->
     call(Z, ?INFLATE_INIT, []).
 
--spec inflateInit(zstream(), zwindowbits()) -> 'ok'.
+-spec inflateInit(Z, WindowBits) -> 'ok' when
+      Z :: zstream(),
+      WindowBits :: zwindowbits().
 inflateInit(Z, WindowBits) -> 
     call(Z, ?INFLATE_INIT2, <<(arg_bitsz(WindowBits)):32>>).
 
--spec inflateSetDictionary(zstream(), binary()) -> 'ok'.
+-spec inflateSetDictionary(Z, Dictionary) -> 'ok' when
+      Z :: zstream(),
+      Dictionary :: binary().
 inflateSetDictionary(Z, Dictionary) -> 
     call(Z, ?INFLATE_SETDICT, Dictionary).
 
@@ -211,11 +240,15 @@ inflateSetDictionary(Z, Dictionary) ->
 inflateSync(Z) -> 
     call(Z, ?INFLATE_SYNC, []).
 
--spec inflateReset(zstream()) -> 'ok'.
+-spec inflateReset(Z) -> 'ok' when
+      Z :: zstream().
 inflateReset(Z) -> 
     call(Z, ?INFLATE_RESET, []).
 
--spec inflate(zstream(), iodata()) -> iolist().
+-spec inflate(Z, Data) -> Decompressed when
+      Z :: zstream(),
+      Data :: iodata(),
+      Decompressed :: iolist().
 inflate(Z, Data) ->
     try port_command(Z, Data) of
 	true -> 
@@ -227,50 +260,81 @@ inflate(Z, Data) ->
 	    erlang:error(badarg) 
     end.
 
--spec inflateEnd(zstream()) -> 'ok'.
+-spec inflateEnd(Z) -> 'ok' when
+      Z :: zstream().
 inflateEnd(Z) ->
     call(Z, ?INFLATE_END, []).
 
--spec setBufSize(zstream(), non_neg_integer()) -> 'ok'.
+-spec setBufSize(Z, Size) -> 'ok' when
+      Z :: zstream(),
+      Size :: non_neg_integer().
 setBufSize(Z, Size) ->
     call(Z, ?SET_BUFSZ, <<Size:32>>).
 
--spec getBufSize(zstream()) -> non_neg_integer().
+-spec getBufSize(Z) -> Size when
+      Z :: zstream(),
+      Size :: non_neg_integer().
 getBufSize(Z) ->
     call(Z, ?GET_BUFSZ, []).
 
--spec crc32(zstream()) -> integer().
+-spec crc32(Z) -> CRC when
+      Z :: zstream(),
+      CRC :: integer().
 crc32(Z) ->
     call(Z, ?CRC32_0, []).
 
--spec crc32(zstream(), binary()) -> integer().
+-spec crc32(Z, Binary) -> CRC when
+      Z :: zstream(),
+      Binary :: binary(),
+      CRC :: integer().
 crc32(Z, Binary) ->
     call(Z, ?CRC32_1, Binary).
 
--spec crc32(zstream(), integer(), binary()) -> integer().
+-spec crc32(Z, PrevCRC, Binary) -> CRC when
+      Z :: zstream(),
+      PrevCRC :: integer(),
+      Binary :: binary(),
+      CRC :: integer().
 crc32(Z, CRC, Binary) when is_binary(Binary), is_integer(CRC) ->
     call(Z, ?CRC32_2, <<CRC:32, Binary/binary>>);
 crc32(_Z, _CRC, _Binary)  ->
     erlang:error(badarg).
 
--spec adler32(zstream(), binary()) -> integer().
+-spec adler32(Z, Binary) -> CheckSum when
+      Z :: zstream(),
+      Binary :: binary(),
+      CheckSum :: integer().
 adler32(Z, Binary) ->
     call(Z, ?ADLER32_1, Binary).
 
--spec adler32(zstream(), integer(), binary()) -> integer().
+-spec adler32(Z, PrevAdler, Binary) -> CheckSum when
+      Z :: zstream(),
+      PrevAdler :: integer(),
+      Binary :: binary(),
+      CheckSum :: integer().
 adler32(Z, Adler, Binary) when is_binary(Binary), is_integer(Adler) ->
     call(Z, ?ADLER32_2, <<Adler:32, Binary/binary>>);
 adler32(_Z, _Adler, _Binary)  ->
     erlang:error(badarg).
 
--spec crc32_combine(zstream(), integer(), integer(), integer()) -> integer().
+-spec crc32_combine(Z, CRC1, CRC2, Size2) -> CRC when
+      Z :: zstream(),
+      CRC :: integer(),
+      CRC1 :: integer(),
+      CRC2 :: integer(),
+      Size2 :: integer().
 crc32_combine(Z, CRC1, CRC2, Len2) 
   when is_integer(CRC1), is_integer(CRC2), is_integer(Len2) ->
     call(Z, ?CRC32_COMBINE, <<CRC1:32, CRC2:32, Len2:32>>);
 crc32_combine(_Z, _CRC1, _CRC2, _Len2) ->
     erlang:error(badarg).
 
--spec adler32_combine(zstream(), integer(), integer(), integer()) -> integer().
+-spec adler32_combine(Z, Adler1, Adler2, Size2) -> Adler when
+      Z :: zstream(),
+      Adler :: integer(),
+      Adler1 :: integer(),
+      Adler2 :: integer(),
+      Size2 :: integer().
 adler32_combine(Z, Adler1, Adler2, Len2) 
   when is_integer(Adler1), is_integer(Adler2), is_integer(Len2) ->
     call(Z, ?ADLER32_COMBINE, <<Adler1:32, Adler2:32, Len2:32>>);
@@ -282,7 +346,9 @@ getQSize(Z) ->
     call(Z, ?GET_QSIZE, []).
 
 %% compress/uncompress zlib with header
--spec compress(binary()) -> binary().
+-spec compress(Binary) -> Compressed when
+      Binary :: binary(),
+      Compressed :: binary().
 compress(Binary) ->
     Z = open(),
     deflateInit(Z, default),
@@ -291,7 +357,9 @@ compress(Binary) ->
     close(Z),
     list_to_binary(Bs).
 
--spec uncompress(binary()) -> binary().
+-spec uncompress(Binary) -> Decompressed when
+      Binary  :: binary(),
+      Decompressed :: binary().
 uncompress(Binary) when byte_size(Binary) >= 8 ->
     Z = open(),
     inflateInit(Z),
@@ -303,7 +371,9 @@ uncompress(Binary) when is_binary(Binary) -> erlang:error(data_error);
 uncompress(_) -> erlang:error(badarg).
 
 %% unzip/zip zlib without header (zip members)
--spec zip(binary()) -> binary().
+-spec zip(Binary) -> Compressed when
+      Binary :: binary(),
+      Compressed :: binary().
 zip(Binary) ->
     Z = open(),
     deflateInit(Z, default, deflated, -?MAX_WBITS, 8, default),
@@ -312,7 +382,9 @@ zip(Binary) ->
     close(Z),
     list_to_binary(Bs).
 
--spec unzip(binary()) -> binary().
+-spec unzip(Binary) -> Decompressed when
+      Binary :: binary(),
+      Decompressed :: binary().
 unzip(Binary) ->
     Z = open(),
     inflateInit(Z, -?MAX_WBITS),
@@ -321,7 +393,9 @@ unzip(Binary) ->
     close(Z),
     list_to_binary(Bs).
     
--spec gzip(iodata()) -> binary().
+-spec gzip(Data) -> Compressed when
+      Data :: iodata(),
+      Compressed :: binary().
 gzip(Data) when is_binary(Data); is_list(Data) ->
     Z = open(),
     deflateInit(Z, default, deflated, 16+?MAX_WBITS, 8, default),
@@ -331,7 +405,9 @@ gzip(Data) when is_binary(Data); is_list(Data) ->
     iolist_to_binary(Bs);
 gzip(_) -> erlang:error(badarg).
 
--spec gunzip(iodata()) -> binary().
+-spec gunzip(Binary) -> Decompressed when
+      Binary :: binary(),
+      Decompressed :: binary().
 gunzip(Data) when is_binary(Data); is_list(Data) ->
     Z = open(),
     inflateInit(Z, 16+?MAX_WBITS),