2.2.client.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
  
#define PORT     8080
#define MAXLINE 1024

int main()
{
    int sockfd;
    char buffer[MAXLINE];
    char msgClient[MAXLINE];
    struct sockaddr_in     servaddr;

    if ( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0 )
    {
        perror("socket creation failed");
        exit(EXIT_FAILURE);
    }
  
    memset(&servaddr, 0, sizeof(servaddr));
      
    // Filling server information
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(PORT);
    servaddr.sin_addr.s_addr = INADDR_ANY;
      
    int n, len;
          
    while(1)
    {
    	scanf("%s", &msgClient);
    	sendto(sockfd, msgClient, strlen(msgClient), MSG_CONFIRM, (const struct sockaddr *) &servaddr, sizeof(servaddr));
    	
    	n = recvfrom(sockfd, (char *)buffer, MAXLINE, MSG_WAITALL, (struct sockaddr *) &servaddr, &len);
    	buffer[n] = '\0';
    	printf("%s\n", buffer);
    	if(strcmp(buffer, "exit") == 0)
    	{
    		sendto(sockfd, "exit", strlen("exit"), MSG_CONFIRM, (const struct sockaddr *) &servaddr, sizeof(servaddr));
    		close(sockfd);
    		return 0;
    	}
    }

    close(sockfd);
    return 0;
}