HP Rp3440-4 - 9000 - 0 MB RAM Programmer's Manual page 171

exit (0);
}
/*
*
*
* This is a variation of the example program called serv.udp.
* This one performs the same function, except that it is
* designed to be called from /etc/inetd. This version does
* not contain a daemon loop, and does not wait for requests
* to arrive on a socket. /etc/inetd does these functions. The
* server simply assumes the socket to receive the message
* from and send the response to is file descriptor 0 when
* the program is started.
* request is already ready to be received from the socket.
*
*/
#include <sys/types.h>
#include <netinet/in.h>
#include <stdio.h>
#include <netdb.h>
#define BUFFERSIZE
int cc;
char buffer[BUFFERSIZE];
struct hostent *hp;
struct sockaddr_in clientaddr_in;/* for client's socket address */
struct in_addr reqaddr;
#define ADDRNOTFOUND
/*
*
*
* This routine receives the request and returns an answer.
* Each request consists of a host name for which the
* requester desires to know the internet address. The
* server will look up the name in its /etc/hosts file,
* and return the internet address to the client. An
* a internet address value of all ones will be returned
* if the host name is not found.
*
*/
main()
{
int addrlen;
/* clear out address structure */
memset ((char *)&clientaddr_in, 0, sizeof(struct sockaddr_in));
/* Note that addrlen is passed as a pointer
* so that the recvfrom call can return the
* size of the returned address.
*/
addrlen = sizeof(struct sockaddr_in);
/* This call will
* return the address of the client,
* and a buffer containing its request.
Chapter 8
Adding a Server Process to the Internet Daemon
S E R V E R . U D P
It also assumes that the client's
1024 /* max size of packets to be received */
/* contains the number of bytes read */
/* buffer for packets to be read into */
/* pointer to info for requested host */
/* for requested host's address */
0xffffffff /* return address for unfound
host */
M A I N
Programming Hints
171