8.16 IO jobs

copy

int main(int argc, const char *argv[])
{
	if(argc != 3)
	{
	  printf("input file error\n");
	  printf("wsage:./a.out srcfile dstfile\n");
	}
	FILE *fp;
	if((fp=fopen(argv[1],"r"))==NULL)
	{
	    perror("fopen error");
		return -1;
	}

	FILE *fp1;
	if((fp1=fopen(argv[2],"w"))==NULL)
	{
	    perror("fopen error");
		return -1;
	}


	char buf;
    while(1)
    {
        fread(&buf,sizeof(buf),1,fp);
		if(feof(fp))
		{
		  break;
		}
        fwrite(&buf,sizeof(buf),1,fp1);
    }
          
        fclose(fp);
		fclose(fp1);

		printf("拷贝成功\n");
		return 0;
}

display time

int main(int argc, const char *argv[])
{
	FILE *fp;
	fp=fopen("./time3.txt","a");
	if(fp==NULL)
	{
		perror("fopen error");
		return -1;
	}
	int i =1;
	while(1)
	{	usleep(1000000);
		time_t systime=time(NULL);
		struct tm *tm_ptr=localtime(&systime);
		fseek(fp,0,SEEK_END);	
		fprintf(fp,"%3d: %4d-%2d-%2d %2d:%2d:%2d\n",i,\
				tm_ptr->tm_year+1900,\
				tm_ptr->tm_mon+1,\
				tm_ptr->tm_mday,\
				tm_ptr->tm_hour,\
				tm_ptr->tm_min,\
				tm_ptr->tm_sec);	
		printf("%3d :%4d-%2d-%2d %02d:%02d:%02d\n",\
				i,\
				tm_ptr->tm_year+1900,\
				tm_ptr->tm_mon+1,\
				tm_ptr->tm_mday,\
				tm_ptr->tm_hour,\
				tm_ptr->tm_min,\
				tm_ptr->tm_sec);
		i++;
	}
	return 0;
}