Stop and Wait Client

#include <arpa/inet.h>
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <sys/socket.h>
#include <unistd.h>
#define PORT 8080

void transfer(int sock){

      int *n,i,e=0,c=0,k=0;
      n=&i;
      printf("Expect\tFrame status\tACK status");
     while((read(sock,n,sizeof(i)))!=0){
     c++;
          if(c==7){
            continue;
          }
          printf("\n%d\t Frame no:%d\t",k,i);
          if(e==i){
          i=(i+1)%2;
          e=i;

          printf("ACK no:%d",i);
          write(sock,n,sizeof(i));
          k++;
          }
          else{
            printf("Wrong frame");
          }
      }

}

int main(int argc, char const* argv[])
{
    int sock = 0, valread, client_fd,n;
    struct sockaddr_in serv_addr;
    char str[5];
    char buffer[1024] = { 0 };
    if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
        printf("\n Socket creation error \n");
        return -1;
    }

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(PORT);

    // Convert IPv4 and IPv6 addresses from text to binary
    // form
    if (inet_pton(AF_INET, "127.0.0.1", &serv_addr.sin_addr)
        <= 0) {
        printf(
            "\nInvalid address/ Address not supported \n");
        return -1;
    }

    if ((client_fd
        = connect(sock, (struct sockaddr*)&serv_addr,
                sizeof(serv_addr)))
        < 0) {
        printf("\nConnection Failed \n");
        return -1;
    }


        transfer(sock);
    // closing the connected socket
    close(client_fd);
    return 0;
}