Initial data commit

Task/Mutex/Erlang/mutex.erl

@@ -0,0 +1,40 @@
+-module( mutex  ).
+
+-export( [task/0] ).
+
+task() ->
+    Mutex = erlang:spawn( fun() -> loop() end ),
+    [erlang:spawn(fun() -> random:seed( X, 0, 0 ), print(Mutex, X, 3) end) || X <- lists:seq(1, 3)].
+
+
+
+loop() ->
+    receive
+    {acquire, Pid} ->
+        Pid ! {access, erlang:self()},
+        receive
+        {release, Pid} -> loop()
+        end
+    end.
+
+mutex_acquire( Pid ) ->
+    Pid ! {acquire, erlang:self()},
+    receive
+    {access, Pid} -> ok
+    end.
+
+mutex_release( Pid ) -> Pid ! {release, erlang:self()}.
+
+print( _Mutex, _N, 0 ) -> ok;
+print( Mutex, N, M ) ->
+    timer:sleep( random:uniform(100) ),
+    mutex_acquire( Mutex ),
+    io:fwrite( "Print ~p: ", [N] ),
+    [print_slow(X) || X <- lists:seq(1, 3)],
+    io:nl(),
+    mutex_release( Mutex ),
+    print( Mutex, N, M - 1 ).
+
+print_slow( X ) ->
+    io:fwrite( " ~p", [X] ),
+    timer:sleep( 100 ).