forking interactive server in c

hallo,

hab ein mittelschweres problem,
wir sollen auf der uni einen simple tcp server basteln der interaktiv sein soll.
das ding kann momentan nur eine message beim client ausspucken, der professor meinte " mochens des mit stdin und stdout "
hat einer von euch eine idee wie sich das lösen lassen könnte ?

code :



#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>
#define MYPORT 3490 // the port users will be connecting to
#define BACKLOG 10 // how many pending connections queue will hold
void sigchld_handler(int s)
{
while(wait(NULL) > 0);
}
int main(void)
{
int sockfd, new_fd; // listen on sock_fd, new connection on new_fd
struct sockaddr_in my_addr; // my address information
struct sockaddr_in their_addr; // connector.s address information
int sin_size;
struct sigaction sa;
int yes=1;
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
{
perror("socket");
exit(1);
}
if (setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1)
{
perror("setsockopt");
exit(1);
}
my_addr.sin_family = AF_INET; // host byte order
my_addr.sin_port = htons(MYPORT); // short, network byte order
my_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP
memset(&(my_addr.sin_zero), '\0', 8); // zero the rest of the struct
if (bind(sockfd, (struct sockaddr*)&my_addr, sizeof(struct sockaddr))== -1)
{
perror("bind");
exit(1);
}
if (listen(sockfd, BACKLOG) == -1)
{
perror("listen");
exit(1);
}

sa.sa_handler = sigchld_handler; // reap all dead processes
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
if (sigaction(SIGCHLD, &sa, NULL) == -1)
{
perror("sigaction");
exit(1);
}
while(1) { // main accept() loop
sin_size = sizeof(struct sockaddr_in);
if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr,&sin_size)) == -1)
{
perror("accept");
continue;
}
printf("server: got connection from %s\n",
inet_ntoa(their_addr.sin_addr));



if (!fork())
{ // this is the child process
close(sockfd); // child doesn.t need the listener
if (send(new_fd, "I foresee Victory\a", 14, 0) == -1)
perror("send");
close(new_fd);
exit(0);
}
close(new_fd); // parent doesn.t need this
}
return 0;
}

zip gapud