에코 Server/Client #2

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

#define BUF_SIZE 30
void error_handling(char *message);

int main(int argc, char *argv[])
{
	int serv_sock;
	char message[BUF_SIZE];
	int str_len;
	socklen_t clnt_adr_sz;
	
	struct sockaddr_in serv_adr, clnt_adr;
	if(argc!=2){
		printf("Usage : %s <port>\n", argv[0]);
		exit(1);
	}
	
	serv_sock=socket(PF_INET, SOCK_DGRAM, 0);
	if(serv_sock==-1)
		error_handling("UDP socket creation error");
	
	memset(&serv_adr, 0, sizeof(serv_adr));
	serv_adr.sin_family=AF_INET;
	serv_adr.sin_addr.s_addr=htonl(INADDR_ANY);
	serv_adr.sin_port=htons(atoi(argv[1]));
	
	if(bind(serv_sock, (struct sockaddr*)&serv_adr, sizeof(serv_adr))==-1)
		error_handling("bind() error");

	while(1) 
	{
		clnt_adr_sz=sizeof(clnt_adr);
		str_len=recvfrom(serv_sock, message, BUF_SIZE, 0, 
								(struct sockaddr*)&clnt_adr, &clnt_adr_sz);
		
		printf("IP: %d PORT: %d\n", ntohl(clnt_adr.sin_addr.s_addr), ntohs(clnt_adr.sin_port));
		sendto(serv_sock, message, str_len, 0, 
								(struct sockaddr*)&clnt_adr, clnt_adr_sz);
		printf("IP: %d PORT: %d\n", ntohl(clnt_adr.sin_addr.s_addr), ntohs(clnt_adr.sin_port));
	}	
	close(serv_sock);
	return 0;
}

void error_handling(char *message)
{
	fputs(message, stderr);
	fputc('\n', stderr);
	exit(1);
}

 

 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

#define BUF_SIZE 30
void error_handling(char *message);

int main(int argc, char *argv[])
{
	int sock;
	char message[BUF_SIZE];
	int str_len;
	socklen_t adr_sz;
	
	struct sockaddr_in serv_adr, from_adr;
	if(argc!=3){
		printf("Usage : %s <IP> <port>\n", argv[0]);
		exit(1);
	}
	
	sock=socket(PF_INET, SOCK_DGRAM, 0);   
	if(sock==-1)
		error_handling("socket() error");
	
	memset(&serv_adr, 0, sizeof(serv_adr));
	serv_adr.sin_family=AF_INET;
	serv_adr.sin_addr.s_addr=inet_addr(argv[1]);
	serv_adr.sin_port=htons(atoi(argv[2]));

	// STUB
	struct sockaddr_in temp_adr;
	memset(&temp_adr, 0, sizeof(temp_adr));
	temp_adr.sin_family=AF_INET;
	temp_adr.sin_addr.s_addr=inet_addr("0.0.0.0");
	temp_adr.sin_port=htons(54192);

	bind(sock, (struct sockaddr *)&temp_adr, sizeof(temp_adr));
	while(1)
	{
		fputs("Insert message(q to quit): ", stdout);
		fgets(message, sizeof(message), stdin);     
		if(!strcmp(message,"q\n") || !strcmp(message,"Q\n"))	
			break;
		
		sendto(sock, message, strlen(message), 0, 
					(struct sockaddr*)&serv_adr, sizeof(serv_adr));
		printf("serv_adr\n");
		printf("IP: %d PORT: %d\n", ntohl(serv_adr.sin_addr.s_addr), ntohs(serv_adr.sin_port));
		adr_sz=sizeof(from_adr);
		str_len=recvfrom(sock, message, BUF_SIZE, 0, 
					(struct sockaddr*)&from_adr, &adr_sz);
		printf("recvfrom\n");
		printf("IP: %d PORT: %d\n", ntohl(from_adr.sin_addr.s_addr), ntohs(from_adr.sin_port));
		message[str_len]=0;
		printf("Message from server: %s", message);
	}	
	close(sock);
	return 0;
}

void error_handling(char *message)
{
	fputs(message, stderr);
	fputc('\n', stderr);
	exit(1);
}