Re: OSS ioctls...

["Richard Cooper" <generic@xersedefixion.com>]

> Did you tried the linuxassembly.org/articles/audio.html? Your code looks  
> very similar and %define's seems to be different.

I must have skimmed throught the list too fast, I didn't realize there was  
an article.  Otherwise I would have read that instead of the massive PDF  
than is the OSS documentation.  It's really quite nice documentation.  It  
just naturally doesn't define the IOCTL numbers.  It's at  
http://www.opensound.com/pguide/oss.pdf if anyone's interested.

But anyway, looking at the example I see there's a $C0040000 or'ed with  
most of the ioctl numbers, and adding that to my numbers fixed everything  
up.

Looking back at the header file I see that some of the IOCTL numbers go  
through a different macro...

   #define SNDCTL_DSP_SETFRAGMENT		_SIOWR('P',10, int)
   #define	_SIOWR(x,y,t)	((int)(SIOC_INOUT|((sizeof(t)&SIOCPARM_MASK)<<16)|(x<<8)|y))
   #define	SIOC_INOUT	(SIOC_IN|SIOC_OUT)
   #define	SIOC_OUT		0x20000000	/* copy out parameters */
   #define	SIOC_IN		0x40000000	/* copy in parameters */

Now as I see it, that should make those IOCTL numbers begin with $6004,  
not $C004, but $6004 doesn't work, only $C004 works.  So I still don't see  
where the $C004 is coming from, but at least I know how to make it work  
now.

Thanks for your help.  I probably wouldn't have figured that out on my own  
until next year or the year after when I happen to stumble upon the  
linuxassembly article, seeing as the header file isn't even correct.