#include 
    
     #include 
     
      int copyFile(const char* dest, const char* src){	FILE* fin = fopen(dest, "r");	FILE* fout = fopen(src, "w");	if (fin && fout)	{		while (!feof(fin))//读到最后一个字符，feof（fin）仍未false		{			fputc(fgetc(fin), fout);		}		fclose(fin);		fclose(fout);		return 0;	}	return -1;}int main(int argc, char* argv[]){	if (argc > 2)	{		if (copyFile(argv[1], argv[2]) != 0)			printf("文件复制失败\n");		else		{			long long len;			FILE *fp;			fp = fopen(argv[1],"r");			fseek(fp,0L,SEEK_END);			len = ftell(fp);			rewind(fp);			printf("输入文件大小：%lld 字节\n",len);			printf("文件内容:\n");			while (!feof(fp))			{				putchar(fgetc(fp));			}			printf("\n");			fclose(fp);			fp = fopen(argv[2],"r");			fseek(fp,0L,SEEK_END);			len = ftell(fp);			rewind(fp);			printf("输出文件大小：%lld 字节\n",len);			printf("文件内容:\n");			while (!feof(fp))			{				putchar(fgetc(fp));			}			printf("\n");			fclose(fp);		}	}}
     
    

命令行：

copy.exe in.txt out.txt

注意out.txt读入了in.txt的文件结束标志EOF，使得两个文件的大小不一样！