Re: dd if=/dev/random of=data.bin bs=512 count=1

From: Jon
Date: Sat May 23 2009 - 15:13:22 EST


Hello KOSAKI,

Thank you for your reply.

KOSAKI Motohiro wrote:
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.

you already have the answer. /dev/random might blocked, /dev/urandom doesn't.

Is this a "feature" of /dev/random ? ..it does not seem very useful to have it able to block for so long.

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

Best regards, Jon
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