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SubjectRe: /dev/random probs in 2.4test(12-pre3)
Followup to:  <>
By author: Igmar Palsenberg <>
In newsgroup:
> > Indeed, you are correct. Is vpnd broken then, for assuming
> > that it can gather the required randomness in one read?
> Yep. It assumes that if the required randommness numbers aren't met a read
> to /dev/random will block.
> And it's not the only program that assumes this : I also did.
> /dev/random is called a blocking random device, which more or less implies
> that it will totally block. I suggest we put this somewhere in the kernel
> docs, since lots of people out there assume that it totally blocks.

That's pretty much ALWAYS wrong -- for pipes, sockets, you name it. A
blocking read() will only block if there is nothing to read at all.

<> at work, <> in private!
"Unix gives you enough rope to shoot yourself in the foot."
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