Subject: Re: bi-directional pipes?
To: Paul Kranenburg <>
From: Jaromir Dolecek <>
List: tech-kern
Date: 02/04/2003 17:43:54
Paul Kranenburg wrote:
> Our pipe(2) system call internally creates data structures to enable
> bi-directional traffic (inherited from FreeBSD). We don't currently
> use this. We don't even expose it at all since the pipe descriptors are
> marked read-only and write-only.
> The question is: do we want to hang on to this?

Definitely no. I disabled the bi-directional stuff by intention,
and made it only allocate buffer memory for one way pipe. I didn't
want to have the structure wildly different to FreeBSD at the
time, that why I kept it the way it is.

Feel free to further simplify the structures. We definitely don't
want to ever support bi-directional pipes. It's unncecessary
memory and CPU waste.

Jaromir Dolecek <>  
-=- We should be mindful of the potential goal, but as the tantric    -=-
-=- Buddhist masters say, ``You may notice during meditation that you -=-
-=- sometimes levitate or glow.   Do not let this distract you.''     -=-