Re: dtrace ioctls

[David Holland <dholland-tech%netbsd.org@localhost>]

On Wed, Oct 19, 2011 at 10:49:53AM +0000, YAMAMOTO Takashi wrote:
 > some dtrace ioctls, including DTRACEIOC_AGGSNAP, are defined as
 > the following.
 > 
 >      #define DTRACEIOC_AGGSNAP       _IOW('x',7,dtrace_bufdesc_t *)
 > 
 > and libdtrace has diffs like the following.
 > 
 >      #if defined(sun)
 >              if (dt_ioctl(dtp, DTRACEIOC_AGGSNAP, buf) == -1) {
 >      #else
 >              if (dt_ioctl(dtp, DTRACEIOC_AGGSNAP, &buf) == -1) {
 >      #endif
 > 
 > they seem weird to me.
 > why can't they be like the following?
 > 
 >      _IOW('x',7,dtrace_bufdesc_t)

I don't see any obvious reason... even though dtrace_bufdesc_t is not
actually a primitive type, it's only a 40-byte structure, so it should
be fine...

-- 
David A. Holland
dholland%netbsd.org@localhost