文件IO——用read与write实现图片拷贝

  1 #include <stdio.h>
  2 #include <sys/types.h>
  3 #include <sys/stat.h>
  4 #include <fcntl.h>
  5 #include <unistd.h>
  6 #include <string.h>
  7 int main(int argc, const char *argv[])
  8 {
  9 
 10     int path= open("./1zh.jpg",O_RDONLY);
 11     if(path < 0)
 12     {
 13         perror("open");
 14         return -1;
 15     }
 16     printf("文件打开成功\n");
 17 
 18     int path1= open("./2.jpg",O_WRONLY | O_CREAT | O_TRUNC, 0777);
 19     if(path1 < 0)
 20     {
 21         perror("open");
 22         return -1;
 23     }
 24     printf("文件打开成功\n");
 25     char arr[32] = "";
 26     ssize_t res = 0;
 27     while(1)
 28     {
 29         bzero(arr,sizeof(arr));  
 30         res = read(path,arr,sizeof(arr));
 31         if(res <0)
 32         {
 33             perror("read");
 34             return -1;
 35         }
 36         else if (res == 0)
 37         {
 38             printf("文件读取完毕\n");
 39             break;
 40         }
 41         write(path1,arr,res);
 42     }
 43     if (close(path) <0)
 44     {
 45         perror("close");
 46         return -1;
 47     }
 48     printf("文件关闭成功\n");
 49 
 50     if (close(path1) <0)
 51     {
 52         perror("close");
 53         return -1;
 54     }
 55     printf("文件关闭成功\n");
 56     return 0;
 57 }
 58