Communication protocol applet and server application

Hello,
I want to read and write on server port such that applet is communicating with a server application.
Can any body suggest me any application level communication protocol or algo so that read and write are syncronised.
There is no blocking b/w I/o streams while clients are reading or writing to server.
shahzad

Look at this 3 pages
http://java.sun.com/docs/books/tutorial/networking/sockets/index.html
http://java.sun.com/products/javacomm/javadocs/API_users_guide.html
http://java.sun.com/docs/books/tutorial/networking/sockets/clientServer.html
Noah

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I have a java applet that connects to a C++ application via Java's ServerSocket and Socket objects. THe C++ application is using the Winsock 2 API. The applet and application are running on an NT workstation (SP 6) and using IE (5.5) For a very simple C++ test applications the communictions work fine. Once more code gets added to the C++ application the portion of the socket that C++ listens to seems to close. Upon performing a recv call the return value is a zero. Microsoft insists this is a sign the Java side has shut down the socket. The Java applet can still receive messages from the C++ app but C++ cannot receive responses from the Java side. Java throws no exceptions and an explicit check of the socket shows no errors. Again, what puzzles me is that it works for simple C++ applications. Are there any known conflicts between Java and C++ in this regard?
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a very simple C++ test applications the communictions work fine. Once more code gets added to the C++ application the portion of the socket that C++ listens to seems to close.
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a recv call the return value is a zero. Microsoft insists this is a sign the Java side has shut down the socket.
A correct implementation of recv should return the number of bytes received, or -1 for an error. A zero return indicates no bytes received not a socket closed/error. This sounds like FUD to me.
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I can see no obvious faults, though the code is incomplete, I don't think it's an sockets implementation issue, at either end, it sounds more likely to be a protocol/handshaking bug in the C++ App.

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hi
thanks for ur reply.
I didnt get any error msg while getting the back the datas.
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Im able to do that.and unable to get the data from server.
Didnt get any error.
can u tell me how to make an application to act as both client and server.
I think im wrong in that part.
thanks a lot

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==========================================
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==========================================
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Communication protocol applet and server application

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