Re: CD-blanking leads to machine freeze with current -git

[Marc Koschewski <marc@osknowledge.org>]

* Doug McNaught <doug@mcnaught.org> [2006-02-11 10:35:19 -0500]:

> Marc Koschewski <marc@osknowledge.org> writes:
> 
> > The cdrecord man page says this:
> >
> > 	Setting the -immed flag will request the command to return
> > 	immediately while the operation proceeds in background, making
> > 	the bus usable for the other devices and avoiding the system
> > 	freeze.  This is an experimental feature which may work or
> > 	not, depending on the model of the CD/DVD writer.  A correct
> > 	solution would be to set up a correct cabling but there seem
> > 	to be notebooks around that have been set up the wrong way by
> > 	the manufacturer.  As it is impossible to fix this problem in
> > 	notebooks, the -immed option has been added.
> 
> > It how can the bus run the command sent on the device 'in the
> >background' when it can only process _one_ request at a time?
> >
> > To me it sound like the foreground process (cdrecord) fork()s a
> >process to blank the CD-RW. Clear. But you said the bus is not able
> >to do so... I'm not getting this.
> 
> Some CD writers are apparently able to release the bus while
> blanking, allowing use of the bus by other devices.  The 'immed' flag
> tries to use this feature.  fork() has nothing to do with it--he's
> talking about the IDE command, not the cdrecord program.

I just thought about fork() as Alan (surely and others) told the IDE bus cannot
run several commands at a time. So fork() was the only left-over I could think
of. I didn't know some devices can kinda 'detach' themselves as long as the
blank is going on...

Things are clear now. OK, more clear. Not clear. ;)

Marc
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