socket 통신 코드 연습--매일 조금씩 진보

 
 
/* */
 
 
#include <stdio.h>
 #include <stdlib.h> 
 
 #include <string.h> 
 
 #include <unistd.h> 
 
 #include <sys/socket.h> 
 
 #include <netinet/in.h> 
 
 #include <arpa/inet.h> 
 
 
 
 void die(char *msg) 
 
 { 
 
 
 perror(msg); 
 
 
 exit(1); 
 
 } 
 
 
 
 
 
 void copy_data(int from,int to) 
 
 { 
 
 
 char buf[1024]; 
 
 
 int amount; 
 
 
 while((amount=read(from,buf,sizeof(buf)))>0) { 
 
 
 if(write(to,buf,amount) !=amount) 
 
 
 { 
 
 
  die("write"); 
 
 
 return; 
 
 
 } 
 
 
 } 
 
 
 if(amount <0) die("read"); 
 
 } 
 
 
 
 
 
 
 
 int main() 
 
 { 
 
 
 int sock,conn,i; 
 
 
 struct sockaddr_in addr; 
 
 
 size_t addr_len =sizeof(addr); 
 
 
 if((sock = socket(PF_INET,SOCK_STREAM,0))<0) 
 
 
 die("socket"); 
 
 
   
 
 
  
 
 
 i=1; 
 
 
 setsocketopt(sock,SOL_SOCKET,SO_REUAEADDR,&i,sizeof(i)); 
 
 
 memset(&addr,0,sizeof(addr)); 
 
 
 addr.sin_family = AF_INET; 
 
 
 addr.sin_addr.s_addr=htonl(INADDR_ANY); 
 
 
 addr.sin_port =htons(8888); 
 
 
 
 
 
 
 if(bind(sock,(struct sockaddr *)&addr,sizeof(addr)))  
 
 
 die("blind"); 
 
 
  
 
 
 
 
 
 
 if (lisetn(socket,5)) 
 
 
 die("listen"); 
 
 
  
 
 
 
 
 
 
 while((conn=accept(sock,(struct sockaddr *)&addr,&addr_len)) >=0){ 
 
 
 printf("Accept %s:%d
",inet_ntoa(addr.sin_addr),addr.sin_port); 
 
 
 copy_data(conn,STDOUT_FILENO); 
 
 
 printf("Done!
"); 
 
 
 close(conn); 
 
 
 } 
 
 
 return 0; 
 
 
 
}
 
 
/* */
 
 
#include <stdil.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 
 
 
 
 int main(int argc,const char *argv[])
 {
 struct sockaddr_in addr;
 int sock;
 if (argc !=2){
 fprintf (stderr,"need an IP address
");
 return -1;
 }
 
 memset(&addr,0,sizeof(addr));
 
 addr.sin_family =AF_INET;
 inet_aton(argv[1],&addr.sin_addr);
 addr.sin_port =htons(8888);
 if ((sock =socket(PF_INET,SOCK_STREAN,0)) <0{
 die("socket");
 }
 if (connect(sock,(struct sockaddr *)&addr,sizeof(addr))){
 die("connect");
 }
 printf("Connected!
);
 copy_data(STDIN_FILENO,sock);
 close(sock);
 return 0;
 }