c ++ string.find（）返回字符串的长度

Question

Hi I am a little confused. My program uses TCP to transfer messages over network. Which is in my opinion irrelevant to my question.

std::stringstream tmp(buf);

            if (tmp.str().find("\r\n") == std::string::npos ) {
                std::cout << " doesnt have ending char" << std::endl;
            }else{
                std::cout << " position of ending char " << tmp.str().find("\r\n") << std::endl;
            }

when a message is read from client, it is pushed to stringstream. Then I am trying to find escape character, unfortunately string.find("\\r\\n") always return length of the string, even though "\\r\\n" is not contained in the buf.

I am using

telnet

to test it, is it possible that this behavior is caused by the telnet?

This is output of my terminal:

Connected to localhost.
Escape character is '^]'.
200 LOGIN
asdadsgdgsd

and this is output from the program:

3001 PORT NUM 
sent message: asdadsgdgsd  END  
position of ending char 11

Answer 1

The string entered in the console then sent and received is

"asdadsgdgsd\r\n"
 012345678901_2_

So the value 11 is correct