What is the usual way of sending data across network?

Question

In C#, I use Binary Serialization to send information across the Stream. This is quite simple as all you do is create a class, serialize it and then deserialize it on the receiving end.

My question is, how can I do something similar in C++? All of the network examples I've seen sends a const char * like;

send("LOGIN");

If I wish to send a string and an integer over network, must I really go to the trouble of converting both to a string, putting a command in front of it, and then sending;

[PSEUDO-CODE]
send("COMMAND|" + tostring(someInteger) + "|" + someString);

Then on the receiving end, splitting this string and parsing? I imagine this would get complicated when I have a vector stored and I want to send this over the network.

What can I do?

Can't help with the transport, but to send objects, just serialise them to XML or better still JSON- that way you just need to send strings — kidshaw, Aug 06 '14 at 06:25
http://stackoverflow.com/questions/523872/how-do-you-serialize-an-object-in-c (c++) http://www.boost.org/doc/libs/1_37_0/libs/serialization/doc/index.html — Roman A. Taycher, Aug 06 '14 at 06:26

Basile Starynkevitch · Accepted Answer · 2014-08-06T06:55:29.110

There are several serialization formats and libraries (but outside of the C++11 standard).

In practice, your question is operating system specific. I guess you use Linux or some Posix system.

I usually recommend serializing in a textual format (easier to debug). Then consider formats like JSON (or YAML, perhaps even XML -but I don't recommend it since it is too complex- etc...) and use libraries like JSONCPP

^{In most cases (but not always!), network transport -milliseconds- is much slower than serialization computing -microseconds- so the textual serialization overhead does not matter much}

If you want some binary serialization (beware of endianess issues), consider perhaps libs11n, XDR, etc... See also htonl(3)

Always document (and keep up to date the documentation) your protocol.

For transport, use TCP/IP (or something above it, e.g. HTTP, 0MQ, etc...). On Linux and Posix, see socket(7) and tcp(7) and read some tutorial on BSD sockets.

You may need to code some event loop using poll(2) (or use an existing event loop framework, libev, libevent, Glib from GTK, QtCore from Qt, etc etc...)

What is the usual way of sending data across network?

3 Answers3