-
Notifications
You must be signed in to change notification settings - Fork 0
/
echo_serv.c
63 lines (53 loc) · 1.34 KB
/
echo_serv.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
#include<stdio.h>
#include<sys/socket.h>
#include<sys/types.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<stdlib.h>
#include<string.h>
#include<time.h>
#include<unistd.h>
#include<errno.h>
void str_echo(int connfd);
int main(int argc, char **argv)
{
int listenfd,connfd,len;
pid_t pid;
struct sockaddr_in servaddr,clientaddr;
len=sizeof(struct sockaddr_in);
listenfd=socket(AF_INET,SOCK_STREAM,0);
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
servaddr.sin_port=htons(0);
bind(listenfd,(struct sockaddr *)&servaddr, sizeof(servaddr));
getsockname(listenfd, (struct sockaddr *)&servaddr, &len);
printf("After bind ephemeral port=%d\n",(int)ntohs(servaddr.sin_port));
listen(listenfd,1);
for(;;){
connfd=accept(listenfd, (struct sockaddr *)&clientaddr,&len);
pid=fork();
if(pid==0)
{
printf("Connection from ::%s: port %d:: child pid %ld \n", inet_ntoa(clientaddr.sin_addr),(int)ntohs(clientaddr.sin_port),(long)getpid());
close(listenfd);
len=sizeof(clientaddr);
str_echo(connfd);
exit(0);
}
close(connfd);
}//for ends here
}//end of main
void str_echo(int connfd)
{
int n;
char buff[1024];
again:
while( (n=read(connfd,buff,1024))>0)
{ write(connfd, buff,n);
write(1, buff,n); // write to stdout
}
if(n<0 && errno==EINTR)
goto again;
else if(n<0)
perror("error:");
}