How to handle the Telnet session with Telnet server

I am using Telnet client from busy-box.I need to create a session with telnet server but session need to be created from c code for particular condition, once the session is created there will 开发者_JS百科be some exchange of data.Once the user presses a particular key then that session should be exit and it should return back to the c code.

please can you help me in that......well i thought of using system("telnet") command from C code but i am not able to control the session.

If you don't need to read from the session, then I suggest the popen() approach.

If you need to write and read, it's going to be tricky.