从文件读取结构

Question

I am trying to write a struct of 4 unsigned integers in a file and then read it back, but I can not read anything.

Here is my code:

// create and write values in superblock
..
Superblock s; // the struct
if(write(file_desc , &superblock , sizeof(Superblock)) == -1) {
  perror("writing superblock");
  exit(1);
}
close(file_desc);
file_desc = open(path_file, O_WRONLY | O_CREAT, 0600);
while ( ( read( file_desc , &s , sizeof(Superblock))) > 0 ) {
  printf("%u %u %u %u\n", s.block_size, s.filename_size, s.max_file_size,
         s.max_dir_file_no);
}

It will not even enter the loop. What am I missing?

Answer 1

您正在打开只写文件（ O_WRONLY ），然后尝试从中read 。