sync; sync; halt vs. shutdown -h now

> A call to halt or shutdown will at some point unmount all mounted
> partitions which in turn will sync the filesystems.
That is correct. Thanks for pointing that out.

Is it true that the option "sync" of the mount command was there
since the very first days of Linux?

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Có phải rằng thời còn dùng Linux kernel cũ, buffering chậm thì phải chạy

sync; sync; halt

còn bây giờ thì cứ

shutdown -h now

thẳng tay cho nó lành?

http://linux.die.net/man/2/sync
http://farrokhi.net/blog/index.php/archives/177