#include        <sys/types.h>   /* basic system data types */
#include        <sys/socket.h>  /* basic socket definitions */
#include        <netinet/in.h>
#include        <stdio.h>
#include        <unistd.h>
#include	<strings.h>
#include	<arpa/inet.h>
#include	<stdlib.h>

#define MAXLINE 1024

ssize_t
readline(int fd, void *vptr, size_t maxlen)
{
  int n, rc;
  char c, *ptr;

  ptr = vptr;
  for (n = 1; n < maxlen; n++) {
    if ( (rc = read(fd, &c, 1)) == 1) {
      *ptr++ = c;
      if (c == '\n')
	break;  /* newline is stored, like fgets() */
    } else if (rc == 0) {
      if (n == 1)
	return(0);      /* EOF, no data read */
      else
	break;          /* EOF, some data was read */
    } else
      return(-1);             /* error, errno set by read() */
  }
  
  *ptr = 0;       /* null terminate like fgets() */
  return(n);
} /* end readline */


void
str_cli(FILE *fp, int sockfd)
{
  char    sendline[MAXLINE], recvline[MAXLINE];

  while (fgets(sendline, MAXLINE, fp) != NULL) {

    write(sockfd, sendline, strlen(sendline));

    if (readline(sockfd, recvline, MAXLINE) == 0)
      {
	printf("str_cli: server terminated prematurely\n");
	exit(-1);
      }
    
    fputs(recvline, stdout);
  }
}


int
main(int argc, char **argv)
{
  int			sockfd;
  struct sockaddr_in	servaddr;
  int 			retval;
  
  if (argc != 2)
    {
      printf("usage: tcpcli <IPaddress>\n");
      exit(-1);
    }
  
  sockfd = socket(AF_INET, SOCK_STREAM, 0);
  if (sockfd == -1) {
     printf("socket() failed.\n");
     exit(-1);
  }

  bzero(&servaddr, sizeof(servaddr));
  servaddr.sin_family = AF_INET;
  servaddr.sin_port = htons(6789);
  // inet_pton(AF_INET, argv[1], &servaddr.sin_addr);
  servaddr.sin_addr.s_addr = inet_addr(argv[1]);

  retval = connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr));
  if (retval == -1) {
     printf("connect() failed.\n");
     exit(-1);
  }

  str_cli(stdin, sockfd);		/* do it all */

  exit(0);
}