在没有在文件中创建漏洞的情况下，在ext4文件系统中从一个C文件系统中增加一个文件的大小，最快的方法是什么?

The fastest way to increase the file size that I know of would be to ftruncate() or lseek() to the desired size and write a single byte. That doesn't fit my needs in this case because the resulting hole in the file doesn't reserve space in the file system.The fastest way to increase the file size that