.\"	$NetBSD: dgramsend.c,v 1.3 2003/08/07 10:30:50 agc Exp $
.\"
.\" Copyright (c) 1986, 1993
.\"	The Regents of the University of California.  All rights reserved.
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.\" modification, are permitted provided that the following conditions
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.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
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.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\"
.\"	@(#)dgramsend.c	8.1 (Berkeley) 6/8/93
.\"
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>

#define DATA "The sea is calm tonight, the tide is full . . ."

/*
 * Here I send a datagram to a receiver whose name I get from the command
 * line arguments.  The form of the command line is dgramsend hostname
 * portnumber 
 */

main(argc, argv)
	int argc;
	char *argv[];
{
	int sock;
	struct sockaddr_in name;
	struct hostent *hp, *gethostbyname();

	/* Create socket on which to send. */
	sock = socket(AF_INET, SOCK_DGRAM, 0);
	if (sock < 0) {
		perror("opening datagram socket");
		exit(1);
	}
	/*
	 * Construct name, with no wildcards, of the socket to send to.
	 * Getnostbyname() returns a structure including the network address
	 * of the specified host.  The port number is taken from the command
	 * line. 
	 */
	hp = gethostbyname(argv[1]);
	if (hp == 0) {
		fprintf(stderr, "%s: unknown host\n", argv[1]);
		exit(2);
	}
	bcopy(hp->h_addr, &name.sin_addr, hp->h_length);
	name.sin_family = AF_INET;
	name.sin_port = htons(atoi(argv[2]));
	/* Send message. */
	if (sendto(sock, DATA, sizeof(DATA), 0, &name, sizeof(name)) < 0)
		perror("sending datagram message");
	close(sock);
}