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main.c

#include"head.h"
#define SER_IP "192.168.8.101"
int main(int argc, const char *argv[])
{
	int ucfd =socket(AF_INET,SOCK_DGRAM,0);
	if(ucfd<0)
	{
		ERR_MSG("socket");
		return -1;
	}
	struct sockaddr_in ucin;
	ucin.sin_family = AF_INET;
	ucin.sin_port = htons(69);
	ucin.sin_addr.s_addr = inet_addr(SER_IP);
	struct sockaddr_in usin;
	socklen_t rlen=sizeof(usin),slen=sizeof(ucin);
	char buf[516];
	short *pa=(short*)buf;
	*pa=htons(1);
	char *pb=buf+2;
	strcpy(pb,argv[1]);
	char *pc=buf+2+strlen(pb)+1;
	strcpy(pc,"octet");
	size_t buf_len =2+strlen(pb)+1+strlen(pc)+1;
	sendto(ucfd,buf,buf_len,0,(struct sockaddr*)&ucin,slen);
	char back_val[516]={0};
	recvfrom(ucfd,back_val,sizeof(back_val),0,(struct sockaddr*)&usin,&rlen);
	if(connect(ucfd,(struct sockaddr*)&usin,rlen)<0)
	{
		ERR_MSG("connect");
		return -1;
	}
	short make_code,c_code;
	make_code = *(short*)back_val;
	c_code =*(short*)(back_val+2);
	int fd = open(argv[1],O_RDWR|O_CREAT|O_TRUNC,0777);
	write(fd,back_val+4,512);
	char back_codes[4];
	size_t res;
	while(1)
	{
		short *ba=(short*)back_codes;
		*ba= htons(4);
		short *bb=(short*)(back_codes+2);
		*bb= *(short*)(back_val+2);
		bzero(back_val,516);
		send(ucfd,back_codes,sizeof(back_codes),0);
		res = recv(ucfd,back_val,sizeof(back_val),0);
		write(fd,back_val+4,512);
		bzero(back_codes,4);
		if(res<516)
		{
			printf("success\n");
			break;
		}
	}
	close(fd);
	close(ucfd);
	return 0;
}