#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

int
main(int argc, char *argv[])
{
	struct sockaddr_in sin;
	char *buffer;
	int fd, length;
	long i, n;

	if (argc != 5) {
		fprintf(stderr, "%s", "Usage: send_udp remote_addr remote_port buf_len send_count\n");
		return (-1);
	}
	if ((fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
		perror("socket");
	}
	length = atoi(argv[3]);
	if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &length, sizeof(int)) < 0) {
		perror("setsockopt");
	}
	memset(&sin, 0, sizeof(struct sockaddr_in));
	sin.sin_family = AF_INET;
#if defined(__FreeBSD__) || defined(__APPLE__)
	sin.sin_len = sizeof(struct sockaddr_in);
#endif
	sin.sin_port = htons(atoi(argv[2]));
	sin.sin_addr.s_addr = inet_addr(argv[1]);
	buffer = calloc(1, length);
	n = atol(argv[4]);
	for (i = 0; i < n; i++) {
		if (sendto(fd, buffer, length, 0, (const struct sockaddr *)&sin,
		    (socklen_t)sizeof(struct sockaddr_in)) != length) {
			perror("send");
		}
	}
	if (close(fd) < 0) {
		perror("close");
	}
	free(buffer);
	return (0);
}