enterID - 개행문자 없애기

echo_selectserv.c

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

#define BUF_SIZE	100
#define SERVER_IP	INADDR_ANY
#define SERVER_PORT	"9987"

void error_handling(char *buf);

int main(/*int argc, char *argv[]*/)
{
	int serv_sock, clnt_sock;
	struct sockaddr_in serv_adr, clnt_adr;
	struct timeval timeout;
	fd_set reads, cpy_reads;

	socklen_t adr_sz;
	int fd_max, str_len, fd_num, i;
	char buf[BUF_SIZE];
	/*if(argc!=2) {
		printf("Usage : %s <port>\n", argv[0]);		
		exit(1);
	}
	printf("argc count: %d\n", argc);*/

	//1. server socket 생성
	serv_sock=socket(PF_INET, SOCK_STREAM, 0);

	//2. server socket 주소 정보 초기화
	memset(&serv_adr, 0, sizeof(serv_adr));
	serv_adr.sin_family=AF_INET;
	serv_adr.sin_addr.s_addr=htonl(SERVER_IP);
	serv_adr.sin_port=htons(atoi(SERVER_PORT));
	
	//3. server socket 주소 정보 binding
	if(bind(serv_sock, (struct sockaddr*) &serv_adr, sizeof(serv_adr))==-1)
		error_handling("bind() error");

	//4. client 접속 대기
	if(listen(serv_sock, 5)==-1)
		error_handling("listen() error");
	printf("server socket listening...\n");

	FD_ZERO(&reads);
	FD_SET(serv_sock, &reads);
	fd_max=serv_sock;

	while(1)
	{
		cpy_reads=reads;
		timeout.tv_sec=5;
		timeout.tv_usec=5000; //위의 timeout.tv_sec 또는 timeout.tv_usec 하나만 써도 됨

		if((fd_num=select(fd_max+1, &cpy_reads, 0, 0, &timeout))==-1) //오류 발생시(-1일때)
			break;
		
		if(fd_num==0) // timeout  발생
			continue;

		for(i=0; i<fd_max+1; i++) // 폴링방식으로 계속 체크. fd_max'+1' 이유: fd_max가 서버라서 서버갯수
		{
			if(FD_ISSET(i, &cpy_reads))
			{
				if(i==serv_sock)     // connection request!
				{
					adr_sz=sizeof(clnt_adr);
					clnt_sock=
						accept(serv_sock, (struct sockaddr*)&clnt_adr, &adr_sz);
					FD_SET(clnt_sock, &reads);
					if(fd_max<clnt_sock)
						fd_max=clnt_sock;
					printf("connected client: %d \n", clnt_sock);
					read(clnt_sock, buf, BUF_SIZE);
					buf[strlen(buf) - 1] = '\0';
					printf("------------------------------\n");
					printf("ID: %s entered\n", buf);
					printf("------------------------------\n");
					memset(buf, 0, BUF_SIZE);
				}
				else    // read message!
				{
					str_len=read(i, buf, BUF_SIZE);
					printf("str_len : %d\n", str_len);
					if(str_len==0)    // close request!
					{
						FD_CLR(i, &reads);
						close(i);
						printf("closed client: %d \n", i);
					}
					else
					{
						write(i, buf, str_len);    // echo!
						printf("ID: %s\n", buf);
						memset(buf, 0, BUF_SIZE);

					}
				}
			}
		}
	}
	close(serv_sock);
	return 0;
}

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

 

 

echo_clint.c

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

#define BUF_SIZE	100
#define SERVER_IP	"127.0.0.1"
#define SERVER_PORT	"9987"
void error_handling(char *message);

int main(/*int argc, char *argv[]*/)
{
	int sock;
	char message[BUF_SIZE];
	int str_len;
	struct sockaddr_in serv_adr;

	/*
	if(argc!=3) {
		printf("Usage : %s <IP> <port>\n", argv[0]);
		exit(1);
	}*/
	
	sock=socket(PF_INET, SOCK_STREAM, 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(SERVER_IP);
	serv_adr.sin_port=htons(atoi(SERVER_PORT));
	
	if(connect(sock, (struct sockaddr*)&serv_adr, sizeof(serv_adr))==-1)
		error_handling("connect() error!");
	else
		puts("Connected...........");
	printf("enter ID: ");
	char id[20] = { 0, };
	fgets(id, 20, stdin);
	write(sock, id, strlen(id));
	id[strlen(id) - 1] = '\0';
	printf("------------------------------\n");
	printf("ID: %s entered\n", id);
	printf("------------------------------\n");
	

	while(1) 
	{
		fputs("Input message(Q to quit): ", stdout);
		fgets(message, BUF_SIZE, stdin);
		
		if(!strcmp(message,"q\n") || !strcmp(message,"Q\n"))
			break;

		write(sock, message, strlen(message));
		str_len=read(sock, message, BUF_SIZE-1);
		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);
}

 

 

개행문자 없애기

1. id[strlen(id) - 1] = '\0';을 server와 clinet  둘 다 추가

2. client에서 write(sock, id, strlen(id)-1);  :  문자열에서 -1한 문자열을 서버로 전송해주기

3.  client는 그대로 두고 server에  아래처럼 추가. 

if(fd_max<clnt_sock) 
fd_max=clnt_sock; 
printf("connected client: %d \n", clnt_sock); 
int readByte = read(clnt_sock, buf, BUF_SIZE); 
char tmpBuf[BUF_SIZE] = {0,}; 
strncpy(tmpBuf, buf, readByte - 1); 
printf("------------------------------\n"); 
printf("ID: %s entered\n", tmpBuf); 
printf("------------------------------\n"); 
memset(buf, 0, BUF_SIZE); 
memset(tmpBuf, 0, BUF_SIZE);

 

 

 

server

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

#define BUF_SIZE	100
#define SERVER_IP	INADDR_ANY
#define SERVER_PORT	"9987"

void error_handling(char *buf);

int main(/*int argc, char *argv[]*/)
{
	int serv_sock, clnt_sock;
	struct sockaddr_in serv_adr, clnt_adr;
	struct timeval timeout;
	fd_set reads, cpy_reads;

	socklen_t adr_sz;
	int fd_max, str_len, fd_num, i;
	char buf[BUF_SIZE];
	/*if(argc!=2) {
		printf("Usage : %s <port>\n", argv[0]);		
		exit(1);
	}
	printf("argc count: %d\n", argc);*/

	//1. server socket 생성
	serv_sock=socket(PF_INET, SOCK_STREAM, 0);

	//2. server socket 주소 정보 초기화
	memset(&serv_adr, 0, sizeof(serv_adr));
	serv_adr.sin_family=AF_INET;
	serv_adr.sin_addr.s_addr=htonl(SERVER_IP);
	serv_adr.sin_port=htons(atoi(SERVER_PORT));
	
	//3. server socket 주소 정보 binding
	if(bind(serv_sock, (struct sockaddr*) &serv_adr, sizeof(serv_adr))==-1)
		error_handling("bind() error");

	//4. client 접속 대기
	if(listen(serv_sock, 5)==-1)
		error_handling("listen() error");
	printf("server socket listening...\n");

	FD_ZERO(&reads);
	FD_SET(serv_sock, &reads);
	fd_max=serv_sock;

	while(1)
	{
		cpy_reads=reads;
		timeout.tv_sec=5;
		timeout.tv_usec=5000; //위의 timeout.tv_sec 또는 timeout.tv_usec 하나만 써도 됨

		if((fd_num=select(fd_max+1, &cpy_reads, 0, 0, &timeout))==-1) //오류 발생시(-1일때)
			break;
		
		if(fd_num==0) // timeout  발생
			continue;

		for(i=0; i<fd_max+1; i++) // 폴링방식으로 계속 체크. fd_max'+1' 이유: fd_max가 서버라서 서버갯수
		{
			if(FD_ISSET(i, &cpy_reads))
			{
				if(i==serv_sock)     // connection request!
				{
					adr_sz=sizeof(clnt_adr);
					clnt_sock=
						accept(serv_sock, (struct sockaddr*)&clnt_adr, &adr_sz);
					FD_SET(clnt_sock, &reads);
					if(fd_max<clnt_sock)
						fd_max=clnt_sock;
					printf("connected client: %d \n", clnt_sock);
					int readByte = read(clnt_sock, buf, BUF_SIZE);
					char tmpBuf[BUF_SIZE] = {0,};
					strncpy(tmpBuf, buf, readByte - 1);
					printf("------------------------------\n");
					printf("ID: %s entered\n", tmpBuf);
					printf("------------------------------\n");
					memset(buf, 0, BUF_SIZE);
					memset(tmpBuf, 0, BUF_SIZE);
				}
				else    // read message!
				{
					str_len=read(i, buf, BUF_SIZE);
					printf("str_len : %d\n", str_len);
					if(str_len==0)    // close request!
					{
						FD_CLR(i, &reads);
						close(i);
						printf("closed client: %d \n", i);
					}
					else
					{
						write(i, buf, str_len);    // echo!
						printf("ID: %s\n", buf);
						memset(buf, 0, BUF_SIZE);

					}
				}
			}
		}
	}
	close(serv_sock);
	return 0;
}

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