11.9线程

#include 
struct File{
	char p1[20];
	char p2[20];
};
/*
 * function:    计算行号
 * @param [ in] 读文件
 * @param [out] 
 * @return      行号
 */
long line(const char*sourtext)
{
	FILE *fp=NULL;
	if((fp=fopen(sourtext,"r"))==NULL)
	{
		perror("fopen");
		return -1;
	}
	fseek(fp,0,SEEK_END);
	long line=0;
	line=ftell(fp);
	fclose(fp);
	return line;
}
/*
 * function:    拷贝文件
 * @param [ in] 读文件,目标文件,写入位置,写的长度
 * @param [out] 
 * @return      成功0,失败-1
 */
int my_copy(const char*sourtext,const char*desttext,int local,int len)
{
	//读模式打开文件1
	FILE *fp=NULL;
	if((fp=fopen(sourtext,"r"))==NULL)
	{
		perror("fopen error");
		return -1;
	}
	//写模式打开文件2
	FILE *fp1=NULL;
	if((fp1=fopen(desttext,"a"))==NULL)
	{
		perror("fopen error");
		return -1;
	}
	//拷贝文件
	fseek(fp,local,SEEK_SET);
	fseek(fp1,local,SEEK_SET);
	while(1)
	{
		char rbuf[128]="";
		fread(rbuf,sizeof(rbuf),1,fp);
		printf("%s",rbuf);
		int temp=strlen(rbuf);
		int sum=0;
		sum=sum+temp;
		if(strlen(rbuf)==0||sum>len)
		{
			fwrite(rbuf,1,temp-(sum-len),fp1);
			break;
		}
		fwrite(rbuf,strlen(rbuf),1,fp1);
	}
	fclose(fp);
	fclose(fp1);
}
void *task1(void *arg)
{
	//线程1
	struct File std=*(struct File*)arg;
	int len=line(std.p1);
	my_copy(std.p1,std.p2,0,len/2);
	pthread_exit(NULL);
}
void *task2(void *arg)
{
	//线程2
	sleep(1);
	struct File std=*(struct File*)arg;
	int len=line(std.p1);
	my_copy(std.p1,std.p2,len/2,len/2);
	pthread_exit(NULL);
}
int main(int argc, const char *argv[])
{
	struct File std;
	strcpy(std.p1,argv[1]);
	strcpy(std.p2,argv[2]);
	//创建俩个线程
	pthread_t tid1=-1;
	if(pthread_create(&tid1,NULL,task1,&std)!=0)
	{
		fprintf(stderr,"create error\n");
		return -1;
	}
	pthread_t tid2=-1;
	if(pthread_create(&tid2,NULL,task2,&std)!=0)
	{
		fprintf(stderr,"create error\n");
		return -1;
	}
	//回收资源
	pthread_join(tid1,NULL);
	pthread_join(tid2,NULL);
	return 0;
}