On Sat, 2 Dec 2000, Igmar Palsenberg wrote:
> > 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.
"totally block"?
For a blocking fd, read(2) has always blocked until some data is
available. There has never been a guarantee, for any driver, that
a read(2) will return the full amount of bytes requested.
There is no need to document this... man read(2) ;-)
Jeff
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This archive was generated by hypermail 2b29 : Sat Dec 02 2000 - 13:06:23 EST