#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>

#define MYPORT  3490
#define BACKLOG 10

int main( void )
{
  int sockfd, new_fd;
  struct sockaddr_in my_addr;
  struct sockaddr_in their_addr;
  int sin_size;

  if ( ( sockfd = socket( AF_INET, SOCK_STREAM, 0 ) ) == -1 ) 
    {
      perror( "socket" );
      exit( 1 );
    }

  my_addr.sin_family = AF_INET;
  my_addr.sin_port = htons( MYPORT );
  my_addr.sin_addr.s_addr = INADDR_ANY;
  memset( &( my_addr.sin_zero ), '\0', 8 );

  if ( bind( sockfd, ( struct sockaddr * )&my_addr, 
	     sizeof( struct sockaddr ) ) == -1 ) 
    {
      perror( "bind" );
      exit( 1 );
    }

  if ( listen( sockfd, BACKLOG ) == -1 ) 
    {
      perror( "listen" );
      exit( 1 );
    }

  while( 1 ) 
    {
      sin_size = sizeof( struct sockaddr_in );
      if ( ( new_fd = accept( sockfd, ( struct sockaddr * )
      			      &their_addr, 
			      &sin_size ) ) == -1 ) 
	{
	  perror( "accept" );
	  continue;
        }

      {
	struct sockaddr_in name;
	sin_size = sizeof( struct sockaddr_in );
	if ( getpeername( new_fd, (struct sockaddr *) &name,
			  &sin_size ) == -1 )
	  {
	    perror( "getpeername" );
	    exit( 1 );
	  }
	
	printf( "server: got connection from %s:%d\n",
		inet_ntoa( name.sin_addr ), 
		ntohs( name.sin_port ) );
      }
      
      /*
	printf( "server: got connection from %s:%d\n", 
	      inet_ntoa( their_addr.sin_addr ), 
	      ntohs( their_addr.sin_port ) );
      */

      if ( send( new_fd, "Hello, world!\n", 14, 0 ) == -1 )
	perror( "send" );
      close( new_fd );
    }
  return 0;
}

/* author: Gustavo Sverzut Barbieri (http://www.gustavobarbieri.com.br) */