Need help about read() and write() on TCP/IP


 
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# 8  
Old 11-07-2010
Just like you can save anything you want in a file, you can send anything you want over a socket. You must decide what bytes of data you will send to mean what. Are you sending lines of text? Are you sending binary structures? Something else? What are you doing?
# 9  
Old 11-08-2010
Basically. the client and server exchange a stream of bytes. That is both send a bunch of bytes, and receive a bunch of bytes. Client and server needs to agree how to decode and interpret this bunch of bytes; this is what we call protocol between the client and the server.

For instance, when you're browsing this very site, a protocol based on TCP called HTTP is used between your web browser and the (apache) server.

So now the question is: how will the client understand the reply "busy update", "select beer", "select quantity" ? How will the client send to the server "light", "black" or "liter","bottle" ? What convention are you using? strings ? something else?

May I recommend this book UNIX Network Programming

Cheers,
Loïc
# 10  
Old 11-08-2010
I finally understood what you guys mean, actually,i want to send lines of text for asking the beer. i have checked something about socket, TCP, but still have no idea for my program, please give me a hand.

thank you
Xiao

---------- Post updated at 04:36 PM ---------- Previous update was at 04:33 PM ----------

yes, that is make me understand what you mean, i'm appreciate for your patience, i need to order beer by lines of text, so how can i do next step?
# 11  
Old 11-14-2010
Dear Lixiao,

start studying and writing your 'hello world' client/server, see for instance Programming IP Sockets on Linux, Part One . Then apply your gained knowledges to solve your particular problem.

You must enter the (socket programming) Path yourself Smilie
This User Gave Thanks to Loic Domaigne For This Post:
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