Socket-programming: recv ()

Question

I have an application in which various objects communicate with each other via sockets, and I use the C programming language. When an object sends a long message to another object, the recv () function can read this message in parts. Therefore, I must rebuild the message on the recipient side, adding all the received parts.

My question is a general socket programming question related to recv (). How does recv () know when a message has been fully read? Should I abort a message with a special character, such as "\ n"? or should I send the message size as a header? What is common practice?

Answer 1

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Answer 2

send() recv() .

:

send(new_socket,message,strlen(message),0);

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Answer 3

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As well as serialization procedures, they give you very convenient extras that C does not provide. For example, their code generator will provide you with routines for copying data types, which is very convenient if this data type is a structure full of pointers that reference allocated memory.

There probably are some free tools and libraries. Google protocol buffers that have a C binding ( http://code.google.com/p/protobuf-c/ ) are a good alternative .