Part B-4

 

Vi p9c.c

#include <stdio.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <string.h>

 

int main(){

  int clientSocket, portNum, nBytes;

  char buffer[1024];

  struct sockaddr_in serverAddr;

  socklen_t addr_size;

 

  clientSocket = socket(PF_INET, SOCK_STREAM, 0);

 

  portNum = 7891;

 

  serverAddr.sin_family = AF_INET;

  serverAddr.sin_port = htons(portNum);

  serverAddr.sin_addr.s_addr = inet_addr("172.16.16.217");

  memset(serverAddr.sin_zero, '\0', sizeof serverAddr.sin_zero);

 

  addr_size = sizeof serverAddr;

  connect(clientSocket, (struct sockaddr *) &serverAddr, addr_size);

 

  while(1){

    printf("Type a sentence to send to server:\n");

    fgets(buffer,1024,stdin);

    printf("You typed: %s",buffer);

 

    nBytes = strlen(buffer) + 1;

 

    send(clientSocket,buffer,nBytes,0);

 

    recv(clientSocket, buffer, 1024, 0);

 

    printf("Received from server: %s\n\n",buffer);

  }

 

  return 0;

}

Vi p9s.c

#include <stdio.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <string.h>

#include <stdlib.h>

 

int main(){

  int welcomeSocket, newSocket, portNum, clientLen, nBytes;

  char buffer[1024];

  struct sockaddr_in serverAddr;

  struct sockaddr_storage serverStorage;

  socklen_t addr_size;

  int i;

 

  welcomeSocket = socket(PF_INET, SOCK_STREAM, 0);

 

  portNum = 7891;

 

  serverAddr.sin_family = AF_INET;

  serverAddr.sin_port = htons(portNum);

  serverAddr.sin_addr.s_addr = inet_addr("172.16.16.217");

  memset(serverAddr.sin_zero, '\0', sizeof serverAddr.sin_zero);

 

  bind(welcomeSocket, (struct sockaddr *) &serverAddr, sizeof(serverAddr));

 

  if(listen(welcomeSocket,5)==0)

    printf("Listening\n");

  else

    printf("Error\n");

 

  addr_size = sizeof serverStorage;

 

  /*loop to keep accepting new connections*/

  while(1){

    newSocket = accept(welcomeSocket, (struct sockaddr *) &serverStorage, &addr_size);

    /*fork a child process to handle the new connection*/

    if(!fork()){

      nBytes = 1;

      /*loop while connection is live*/

      while(nBytes!=0){

        nBytes = recv(newSocket,buffer,1024,0);

 

        for (i=0;i<nBytes-1;i++){

buffer[i] = toupper(buffer[i]);

        }

 

        send(newSocket,buffer,nBytes,0);

      }

      close(newSocket);

      exit(0);

    }

    /*if parent, close the socket and go back to listening new requests*/

    else{

      close(newSocket);

    }

  }

 

  return 0;

}