>From [EMAIL PROTECTED] Fri Feb 12 23:35:38 1999
>From: Monty <[EMAIL PROTECTED]>

>>>I think you misunderstand.  I'm clobbering the transfer buffer *very
>>>much on purpose* to get data on the actual DMA transfer count for all
>>>reads.  This is why Paranoia has access to the actual transfer size
>>>under Linux.  The way I do it, though, is very sensitive to kernel
>>>implementation and violates all sorts of good programming sense.  It
>>>just happens to work and is too useful not to use.
>>
>>How do you distinguish between the NULL charaters you inserted and the 
>>NULL characters you got from the device?

>I'm not using NULLs ;-) I use whatever value I least expect to see at
>the end of a specific transfer.  Note that I'm not 100% proof to a
>'false positive', only 99.9% (in most situations, like reading the
>TOC, I am proof).  I accept the false positive in some CDDA data
>transfers as a situation I must deal with in other ways; I'd rather
>catch all the errors (with a few bogus errors thrown in) than miss a
>few errors now and then.

>>Are you using radioactive NULL's ?

>Yes, absolutely ;-) See:

>http://www.mit.edu/afs/sipb/user/xiphmont/radioactive_null.gif

Looks cool but (specially the second argument to memcpy().
Unfortunately, this would make the code non-portable to K&R only systems.

>>Let's assume you want to talk to your second 'hme' Interface.
>>        HME stands for Happy Meal Ethernet.

>I was reading this during the Day Job's weekly development meeting and
>started giggling uncontrollably :-)

It is really the successor of a beta-development chip called BIG MAC :-)
And you would aggree that that's a neat mame for a BIG (100MB) 
Medium Access Controller. You see, Sun guys still have some sort of humor.

BTW: did you know that the SYSvr4 kernel is mostly based on the SunOS 4.0
object oriented memory and mmap system where Sun introduced a kernel function 
called as_hole() that is used to find a hole in the address space of a process 
that may be used for an mmap(). 

When AT&T and Sun made the contract for SVR4, AT&T forced Sun to rename that function
to as_gap().

J�rg

 EMail:[EMAIL PROTECTED] (home) J�rg Schilling D-13353 Berlin
       [EMAIL PROTECTED]               (uni)  If you don't have iso-8859-1
       [EMAIL PROTECTED]           (work) chars I am J"org Schilling
 URL:  http://www.fokus.gmd.de/usr/schilling   ftp://ftp.fokus.gmd.de/pub/unix

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