Followup to:  <[EMAIL PROTECTED]>
By author:    Igmar Palsenberg <[EMAIL PROTECTED]>
In newsgroup: linux.dev.kernel
>
> > 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.

        -hpa
-- 
<[EMAIL PROTECTED]> at work, <[EMAIL PROTECTED]> in private!
"Unix gives you enough rope to shoot yourself in the foot."
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