Initial data commit

Task/Echo-server/Haskell/echo-server-2.hs

@@ -0,0 +1,18 @@
+global mlck, nCons
+
+procedure main()
+    mlck := mutex()
+    nCons := 0
+    while f := open(":12321","na") do {
+        handle_client(f)
+        critical mlck: if nCons <= 0 then close(f)
+        }
+end
+
+procedure handle_client(f)
+    critical mlck: nCons +:= 1
+    thread {
+        select(f,1000) & repeat writes(f,reads(f))
+        critical mlck: nCons -:= 1
+        }
+end