diff --git a/luxtronik/__init__.py b/luxtronik/__init__.py
index 4cb9fb0e..6754531d 100755
--- a/luxtronik/__init__.py
+++ b/luxtronik/__init__.py
@@ -36,19 +36,22 @@
 
 def is_socket_closed(sock: socket.socket) -> bool:
     """Check is socket closed."""
+    # Alternative to socket.MSG_DONTWAIT in recv.
+    # Works on Windows and Linux.
+    sock.setblocking(False)
     try:
         # this will try to read bytes without blocking and also without removing them from buffer
-        data = sock.recv(LUXTRONIK_SOCKET_READ_SIZE_PEEK, socket.MSG_DONTWAIT | socket.MSG_PEEK)
-        if len(data) == 0:
-            return True
+        data = sock.recv(LUXTRONIK_SOCKET_READ_SIZE_PEEK, socket.MSG_PEEK)
+        is_closed = len(data) == 0
     except BlockingIOError:
-        return False  # socket is open and reading from it would block
+        is_closed = False  # socket is open and reading from it would block
     except ConnectionResetError:  # pylint: disable=broad-except
-        return True  # socket was closed for some other reason
+        is_closed = True  # socket was closed for some other reason
     except Exception as err:  # pylint: disable=broad-except
         LOGGER.exception("Unexpected exception when checking if socket is closed", exc_info=err)
-        return False
-    return False
+        is_closed = False
+    sock.setblocking(True)
+    return is_closed
 
 
 class LuxtronikData:
diff --git a/luxtronik/__main__.py b/luxtronik/__main__.py
index 872e3450..075145d7 100755
--- a/luxtronik/__main__.py
+++ b/luxtronik/__main__.py
@@ -25,8 +25,8 @@ def main() -> int:
         description="CLI for Luxtronik controllers",
         usage="""luxtronik <command> [<args>]
         The supported commands are:
-        dump       Dump all available data from the Luxtronik controller 
-        changes    Dump all value changes from Luxtronik controller  
+        dump       Dump all available data from the Luxtronik controller
+        changes    Dump all value changes from Luxtronik controller
         discover   Discover Luxtronik controllers on the network (via magic packet) and output results
         """,
     )
@@ -47,3 +47,6 @@ def main() -> int:
     sys.argv.pop(1)
     # call the corresponding command
     commands[args.command]()
+
+if __name__ == "__main__":
+    main()
\ No newline at end of file
diff --git a/tests/test_socket_interaction.py b/tests/test_socket_interaction.py
index 88c0402e..e7e2f60b 100644
--- a/tests/test_socket_interaction.py
+++ b/tests/test_socket_interaction.py
@@ -36,6 +36,7 @@ def __init__(self, prot, stream):
         assert stream == socket.SOCK_STREAM
         self._connected = False
         self._buffer = b""
+        self._blocking = False
 
         # Offer some more entries
         self._num_paras = len(Parameters()._data) + 10
@@ -44,6 +45,9 @@ def __init__(self, prot, stream):
 
         self.written_values = {}
 
+    def setblocking(self, blocking):
+        self._blocking = blocking
+
     def connect(self, info):
         assert not self._connected
 
@@ -127,7 +131,7 @@ def sendall(self, data):
     def recv(self, cnt, flag=0):
         assert self._connected
 
-        if (flag & socket.MSG_DONTWAIT) and len(self._buffer) < cnt:
+        if (not self._blocking) and len(self._buffer) < cnt:
             raise BlockingIOError("Not enough bytes in buffer.")
 
         assert len(self._buffer) >= cnt