[mythtv] [mythtv-commits] mythtv commit: r18315 by paulh

cal cal at graggrag.com
Mon Sep 22 06:53:10 UTC 2008


Nigel Pearson wrote:
>> Cal, I think your version always returns false...
>>  VB_MEDIA&VB_EXTRA => 0
> 
> 
> Oops. Yep. Left to right, so its the same as
> 
> ((print_verbose_messages & VB_MEDIA) & VB_EXTRA)
> 
> The first expression is either 0 or 0x00800000.
> Either of these ANDed with 0x40000000 is 0!
> 
> 
> 
> I'm still lost about this form, though:
> (print_verbose_messages & (VB_MEDIA+VB_EXTRA))
> 
> 0x00800000 + 0x40000000 should be 0x40800000,
> no matter how the compiler slices and dices it?

FE_OPTS: -v important,audio,nodatabase,extra
print_verbose_messages 40000401

FE_OPTS: -v important,audio,nodatabase,media,extra
print_verbose_messages 40800401

VB_MEDIA   800000
VB_EXTRA 40000000

> I originally started using the A+B form because
> it makes it clearer in a VERBOSE call that both
> values are required.
which makes perfect sense in the normal VERBOSE() call, but here we're indulging in a selective process, so ANDing is the only sensible way.

cheers, and no more from me!



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