On 2008-04-22 15:45 +0200, Matthew Macdonald-Wallace wrote: > On Tue, 22 Apr 2008 21:35:31 +0800 > paragasu <[EMAIL PROTECTED]> wrote: > >> now i am wondering. whether it is because the command i just executed >> or my hard disk is really dying? > > It could be either. The command you typed effectively formatted the > disk.
I don't think so. > /dev/null contains no data. It is the Linux equivalent of a black > hole. If you send the output of /dev/null to a file (which is exactly > what you have done) with a single chevron (>), it will overwrite > anything that exists in that file (in this case the entire contents of > your disk). Only true for an ordinary file and because it's the shell that truncates the file before the redirection. Since you cannot read anything from /dev/null, catting it to device files is harmless. It's a different story with /dev/zero instead of /dev/null ... > If you use a double chevron (>>) you will append the > contents of /dev/null to the end of the file (in this case, your disk). But because you append nothing, that's actually a no-op. Sven -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
