#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>

#define SA struct sockaddr
int listenfd, connfd;

void function(char* str)
{
  char readbuf[256];
  char writebuf[256];
  strcpy(readbuf, str);
  sprintf(writebuf, readbuf);
  write(connfd, writebuf, strlen(writebuf));
}

int main(int argc, char* argv[])
{
  char line[1024];
  struct sockaddr_in servaddr;
  ssize_t n;
  
  listenfd = socket(AF_INET, SOCK_STREAM, 0);
  bzero(&servaddr, sizeof(servaddr));
  servaddr.sin_family = AF_INET;
  servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
  servaddr.sin_port = htons(7776);
  bind(listenfd,
        (SA*)&servaddr, sizeof(servaddr));
  listen(listenfd, 1024);
  
  for(;;)
  {
    connfd = accept(listenfd, (SA*)NULL, NULL);
    write(connfd, "> ", 2);
    n = read(connfd, line, sizeof(line)-1);
    line[n] = 0;
    function(line);
    close(connfd);
  }
}