494     struct vfs_file_t *file_ptr = (struct vfs_file_t *)kzalloc(sizeof(struct vfs_file_t), 0);  in do_open()  local
498     file_ptr->dEntry = dentry;  in do_open()
499     file_ptr->mode = flags;  in do_open()
501     file_ptr->file_ops = dentry->dir_inode->file_ops;  in do_open()
504     if (file_ptr->file_ops && file_ptr->file_ops->open)  in do_open()
505         errcode = file_ptr->file_ops->open(dentry->dir_inode, file_ptr);  in do_open()
509         kfree(file_ptr);  in do_open()
514     if (file_ptr->mode & O_TRUNC) // 清空文件  in do_open()
515         file_ptr->dEntry->dir_inode->file_size = 0;  in do_open()
517     if (file_ptr->mode & O_APPEND)  in do_open()
518         file_ptr->position = file_ptr->dEntry->dir_inode->file_size;  in do_open()
520         file_ptr->position = 0;  in do_open()
522     int fd_num = process_fd_alloc(file_ptr);  in do_open()
527         kfree(file_ptr);  in do_open()
556     struct vfs_file_t *file_ptr = current_pcb->fds[fd_num];  in vfs_close()  local
559     if (file_ptr->file_ops && file_ptr->file_ops->close)  in vfs_close()
560         ret = file_ptr->file_ops->close(file_ptr->dEntry->dir_inode, file_ptr);  in vfs_close()
562     kfree(file_ptr);  in vfs_close()