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From: Jon Grant <jg@jguk.org>
To: linux-kernel@vger.kernel.org
Subject: dd if=/dev/random of=data.bin bs=512 count=1
Date: Sun, 17 May 2009 15:22:26 +0000	[thread overview]
Message-ID: <19ac3f7a0905170822q28255239nea01b56d52e3ddf8@mail.gmail.com> (raw)

Hello

Issuing this command, I expected to get a file 4096 bytes in size.
Could someone let me know if I have missed something..? Or is there a
problem with using /dev/random this way?

if I have a count=10 it hangs forever (several hours).

Changing to use /dev/urandom and it generates the file ok.

Please include my email address in replies,  as I'm not a member of this list.

Best regards, Jon

$ dd if=/dev/random of=data.bin bs=512 count=1
0+1 records in
0+1 records out
8 bytes (8 B) copied, 4.47366 s, 0.0 kB/s

$ dd --version
dd (coreutils) 6.10

$ uname -a
Linux ubuntu 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:57:59 UTC
2009 i686 GNU/Linux

             reply	other threads:[~2009-05-17 15:22 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-05-17 15:22 Jon Grant [this message]
2009-05-17 16:01 ` KOSAKI Motohiro
2009-05-23 19:12   ` Jon
2009-05-23 19:20     ` Samuel Thibault
2009-05-23 19:38     ` Matt Mackall
2009-05-24  0:59     ` Bill Davidsen
2009-05-17 16:27 ` Bernd Eckenfels

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