1 #include <stdio.h>
 2 
 3 int main(int argc,char *argv)
 4 {
 5     //以只读的方式打开被复制的文件
 6     FILE *srcFd = fopen("./source.txt","r");
 7     if(NULL == srcFd)
 8     {
 9         printf("open source file failed\n");
10         return -1;
11     }
12 
13     //以读写的方式创建一个不存在的文件
14     FILE *dstFd = fopen("./save.txt","w+");
15     if(NULL == dstFd)
16     {
17         printf("open save file failed\n");
18         return -1;
19     }
20 
21     //进行获取文件大小的操作
22     fseek(srcFd,0,SEEK_END);       //将光标移动到文件末尾
23     long fileSize = ftell(srcFd);  //获取文件的大小
24     fseek(srcFd,0,SEEK_SET);       //将光标恢复到文件的开头
25 
26     //开辟一个新空间(动态开辟)
27     char *dataBuf = (char *)calloc(1,fileSize+1);
28     if(NULL == dataBuf)
29     {
30         printf("calloc a memory failed\n");
31         return -1;
32     }
33 
34     //读取文件的内容
35     long retSize = fread(dataBuf,1,fileSize,srcFd);
36     if(retSize != fileSize)
37     {
38         printf("read file context failed\n");
39         return -1;
40     }
41 
42     //写入保存文件中
43     retSize = fwrite(dataBuf,1,fileSize,dstFd);
44     if(retSize != fileSize)
45     {
46         printf("write context in file failed\n");
47         return -1;
48     }
49 
50     //关闭文件和释放内存空间
51     fclose(srcFd);
52     fclose(dstFd);
53 
54     free(dataBuf);
55 
56     return 0;    
57 }