udp_send_netparam.c

使用udp的broadcast方式写的c程序

#include <sys/types.h> 

#include <sys/socket.h> 

#include <netinet/in.h> 

#include <errno.h> 

#include <stdio.h> 

#include <unistd.h> 

#include <stdlib.h>

#include <netdb.h>

#include "msgstruct.h"


int udp_send_ip(char *ipaddress, nettype *sendnetparam,unsigned short int port) 

{ 

	int sockfd,n; 
	struct sockaddr_in server_addr;
	struct hostent *host; 
	char *buffer;
	
	buffer = ipaddress;

	/*gethostbyname可通过名称得到主机的IP地址*/
	host=gethostbyname(ipaddress); 

	/*创建套接字*/
	sockfd=socket(AF_INET,SOCK_DGRAM,0); 

	if(sockfd<0) 
	{ 
		printf("Socket Error:%s\n",strerror(errno)); 
		exit(1); 
	}

	/* 填充服务端的资料 */ 
	bzero(&server_addr,sizeof(struct sockaddr_in)); 
	server_addr.sin_family=AF_INET; 
	//server_addr.sin_port=htons(UDP_PORT); 
	server_addr.sin_port=port; 
	server_addr.sin_addr=*((struct in_addr *)host->h_addr);

	/*向服务器端发送数据报*/
	n=sendto(sockfd, sendnetparam, sizeof(nettype), 0,(struct sockaddr *)&server_addr,sizeof(struct sockaddr)); 
	
	//printf("sent %d bytes to %s\n",n,inet_ntoa(server_addr.sin_addr)); 
	//printf("send Num.=%d\nMAC->%s\n", n,sendnetparam->ip_value);
	
	close(sockfd); 
	return 0;

}