// Open an unbound TCP socket
 
      if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
         pdie("Opening stream socket");
 
 
      // Prepare for connection to server
 
      bzero((char *) &server, sizeof(server));
      server.sin_family = AF_INET;
      if ((hp = gethostbyname(argv[1])) == NULL) 
 
      {
         sprintf(buf, "%s: unknown host\n", argv[1]);
         die(buf);
      }//end preparation
 
      bcopy(hp->h_addr, &server.sin_addr, hp->h_length);
      server.sin_port = htons((u_short) SERVER_PORT);
 
      // Establish connection to server
 
      if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 
0)
         pdie("Connecting stream socket");
 
      // What socket number am I talking on?
 
      clientLen = sizeof(client);
      if (getsockname(sock, (struct sockaddr *) &client, &clientLen))
         pdie("Getting socket name");
 
      if (clientLen != sizeof(client))
         die("getsockname() overwrote name structure");
 
      printf("Client socket has port %hu\n", ntohs(client.sin_port));
 
 
int name = ntohs(client.sin_port);
printf("Now the client name is %d\n\n", name);
gets (msg);
 
while (msg != "q")
{
      /* Write out message. */
      if (write(sock, msg, sizeof(msg)) < 0)
         pdie("Writing on stream socket");
 
      /* Prepare buffer and read from it. */
      bzero(buf, sizeof(buf));
      if (read(sock, buf, BUFFER_SIZE) < 0)
         pdie("Reading stream message");
 
      printf("User %d says: %s\n", name, buf);
 
gets(msg);      
}
      close(sock);
 
 
   exit(0);
 
}

// Wait here for the user to enter a message
gets (msg);
 
while (msg != "q")
{
      /* Write out message. */
      if (write(sock, msg, sizeof(msg)) < 0)
         pdie("Writing on stream socket");
 
      /* Prepare buffer and read from it. */
      bzero(buf, sizeof(buf));
      if (read(sock, buf, BUFFER_SIZE) < 0)
         pdie("Reading stream message");
 
      printf("User %d says: %s\n", name, buf);
 
// Wait here for the user to enter a message
gets(msg);      
}

loop forever
    if there is user input data available:
        if the user input is an 'enter':
            if the input buffer contains 'q':
                break the loop
            send the input buffer
        else if the user input is a 'backspace':
            if the input buffer is not empty:
                remove the last character from the input buffer
        else if the user input is a printable character:
            add the character to the input buffer
    if the socket is closed:
        break the loop
    if the socket has data:
        read the data from the socket
        display the data to the user

  for ( ; ; ) {
 
    gets ( msg );   /* IO_1 */
    if ( strcmp ( msg, "q" ) == 0 ) break;
 
    write ( ... );  /* IO_2 */
 
    read ( ... );   /* IO_3 */
    printf ( ... ); /* IO_4 */
  }

 
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/time.h>
#include <pthread.h>
 
 
void*
KeyboardThread (void *unused)
{
    printf ("In keyboard thread\nPress Enter...");
    getchar();
    printf ("Exiting keyboard thread\n:);
    return NULL; /* Or pthread_exit(NULL) */
}
 
 
pthread_t
StartKeyboardThread (void)
{
    pthread_t thread;
    if (pthread_create (&thread,        /* Thread id */
                        NULL,           /* Default attributes */
                        KeyboardThread, /* Thread start routine */
                        NULL)           /* Arg to start routine */
            != 0)
    {
        perror ("StartKeyboardThread");
        exit (-1);
    }
    return thread;
}
 
 
int
main (void)
{
    /* To start it */
    pthread_t thread = StartKeyboardThread();
 
    /* And when you want to kill it */
    pthread_cancel (thread);
 
    return 0;
}