Thread: Sockets

Hi i wrote a server for a simple chat program and im having a little trouble with my buffer that im sending back and forth. My buffer takes in what the person says and writes it to the other person. But im having trouble with over lapping when i say something shorter then the last statment to the other person. I have tried searching for a null character at the end of each buffer but for some reason thats not working here is my code that is having the problem. Each time i write it needs to be the exact size of the character array that is being sent and strlen() isn't working for some reason. if you need any more information just ask me.

Code:

{

                char buf[] = "Start chatting now\n";
                write( io_sd, buf, strlen( buf ) );
                write( io_sd2, buf, strlen( buf ) );
                do
                {
                        read( io_sd, buf_io, cap);
                        for(i=0; i<cap; i++)
                        {
                                tmp[i] = buf_io[i];
                                count++;
                                if(tmp[i] == '\0')
                                {
                                        break;
                                }
                        }
                        printf("%d", count);
                        write( io_sd2, buf_io, count );
                        read( io_sd2, buf_io, cap );
                        for(i=0; i<cap; i++)
                        {
                                tmp[i] = buf_io[i];
                                count++;
                                if(tmp[i] == '\0')
                                {
                                        break;
                                }
                        }
                        printf("%d", count);

                        write( io_sd, buf_io, count );

                }while(1);

        }

here are some test runs

Code:

Person #1

[ ~]$ telnet localhost 15003
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
Start chatting now
test
this is a longer test
shorter test

Person #2
[ ~]$ telnet localhost 15003
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
Start chatting now
test
this is a longer test
shorter test
er test
Mab8v¸ b8èÄAb8C

If you're reading from the keyboard, shouldn't you be looking for \n rather than \0? More importantly, read will tell you how many characters were read; why not use that information?

OK well i got my problem fixed, and the last thing i need to do is get this to quit out when someone types quit. i tried if(strcmp(buf_io, "quit") == 0) then break; but this wont work for some odd reason.

I like vart's answer better. Also: if you're using count as a parameter that gets added to, shouldn't it get reset to 0 every now and again?

Originally Posted by Dr Saucie

OK well i got my problem fixed, and the last thing i need to do is get this to quit out when someone types quit. i tried if(strcmp(buf_io, "quit") == 0) then break; but this wont work for some odd reason.

I'd bet buf_io has an \n at the end of it.

tried the \n nothing happened still

Originally Posted by Dr Saucie

tried the \n nothing happened still

Then debug to see what value is in your variable. See what value check has (if you managed to get that reset each time).